Sample records for excessive computation time

  1. How parents can affect excessive spending of time on screen-based activities.

    PubMed

    Brindova, Daniela; Pavelka, Jan; Ševčikova, Anna; Žežula, Ivan; van Dijk, Jitse P; Reijneveld, Sijmen A; Geckova, Andrea Madarasova

    2014-12-12

    The aim of this study is to explore the association between family-related factors and excessive time spent on screen-based activities among school-aged children. A cross-sectional survey using the methodology of the Health Behaviour in School-aged Children study was performed in 2013, with data collected from Slovak (n = 258) and Czech (n = 406) 11- and 15-year-old children. The effects of age, gender, availability of a TV or computer in the bedroom, parental rules on time spent watching TV or working on a computer, parental rules on the content of TV programmes and computer work and watching TV together with parents on excessive time spent with screen-based activities were explored using logistic regression models. Two-thirds of respondents watch TV or play computer games at least two hours a day. Older children have a 1.80-times higher chance of excessive TV watching (CI: 1.30-2.51) and a 3.91-times higher chance of excessive computer use (CI: 2.82-5.43) in comparison with younger children. More than half of children have a TV (53%) and a computer (73%) available in their bedroom, which increases the chance of excessive TV watching by 1.59 times (CI: 1.17-2.16) and of computer use by 2.25 times (CI: 1.59-3.20). More than half of parents rarely or never apply rules on the length of TV watching (64%) or time spent on computer work (56%), and their children have a 1.76-times higher chance of excessive TV watching (CI: 1.26-2.46) and a 1.50-times greater chance of excessive computer use (CI: 1.07-2.08). A quarter of children reported that they are used to watching TV together with their parents every day, and these have a 1.84-times higher chance of excessive TV watching (1.25-2.70). Reducing time spent watching TV by applying parental rules or a parental role model might help prevent excessive time spent on screen-based activities.

  2. Attentional bias in excessive Internet gamers: Experimental investigations using an addiction Stroop and a visual probe.

    PubMed

    Jeromin, Franziska; Nyenhuis, Nele; Barke, Antonia

    2016-03-01

    Background and aims Internet Gaming Disorder is included in the Diagnostic and statistical manual of mental disorders (5 th edition) as a disorder that merits further research. The diagnostic criteria are based on those for Substance Use Disorder and Gambling Disorder. Excessive gamblers and persons with Substance Use Disorder show attentional biases towards stimuli related to their addictions. We investigated whether excessive Internet gamers show a similar attentional bias, by using two established experimental paradigms. Methods We measured reaction times of excessive Internet gamers and non-gamers (N = 51, 23.7 ± 2.7 years) by using an addiction Stroop with computer-related and neutral words, as well as a visual probe with computer-related and neutral pictures. Mixed design analyses of variance with the between-subjects factor group (gamer/non-gamer) and the within-subjects factor stimulus type (computer-related/neutral) were calculated for the reaction times as well as for valence and familiarity ratings of the stimulus material. Results In the addiction Stroop, an interaction for group × word type was found: Only gamers showed longer reaction times to computer-related words compared to neutral words, thus exhibiting an attentional bias. In the visual probe, no differences in reaction time between computer-related and neutral pictures were found in either group, but the gamers were faster overall. Conclusions An attentional bias towards computer-related stimuli was found in excessive Internet gamers, by using an addiction Stroop but not by using a visual probe. A possible explanation for the discrepancy could lie in the fact that the visual probe may have been too easy for the gamers.

  3. Attentional bias in excessive Internet gamers: Experimental investigations using an addiction Stroop and a visual probe

    PubMed Central

    Jeromin, Franziska; Nyenhuis, Nele; Barke, Antonia

    2016-01-01

    Background and aims Internet Gaming Disorder is included in the Diagnostic and statistical manual of mental disorders (5th edition) as a disorder that merits further research. The diagnostic criteria are based on those for Substance Use Disorder and Gambling Disorder. Excessive gamblers and persons with Substance Use Disorder show attentional biases towards stimuli related to their addictions. We investigated whether excessive Internet gamers show a similar attentional bias, by using two established experimental paradigms. Methods We measured reaction times of excessive Internet gamers and non-gamers (N = 51, 23.7 ± 2.7 years) by using an addiction Stroop with computer-related and neutral words, as well as a visual probe with computer-related and neutral pictures. Mixed design analyses of variance with the between-subjects factor group (gamer/non-gamer) and the within-subjects factor stimulus type (computer-related/neutral) were calculated for the reaction times as well as for valence and familiarity ratings of the stimulus material. Results In the addiction Stroop, an interaction for group × word type was found: Only gamers showed longer reaction times to computer-related words compared to neutral words, thus exhibiting an attentional bias. In the visual probe, no differences in reaction time between computer-related and neutral pictures were found in either group, but the gamers were faster overall. Conclusions An attentional bias towards computer-related stimuli was found in excessive Internet gamers, by using an addiction Stroop but not by using a visual probe. A possible explanation for the discrepancy could lie in the fact that the visual probe may have been too easy for the gamers. PMID:28092198

  4. Associations between parental rules, style of communication and children's screen time.

    PubMed

    Bjelland, Mona; Soenens, Bart; Bere, Elling; Kovács, Éva; Lien, Nanna; Maes, Lea; Manios, Yannis; Moschonis, George; te Velde, Saskia J

    2015-10-01

    Research suggests an inverse association between parental rules and screen time in pre-adolescents, and that parents' style of communication with their children is related to the children's time spent watching TV. The aims of this study were to examine associations of parental rules and parental style of communication with children's screen time and perceived excessive screen time in five European countries. UP4FUN was a multi-centre, cluster randomised controlled trial with pre- and post-test measurements in each of five countries; Belgium, Germany, Greece, Hungary and Norway. Questionnaires were completed by the children at school and the parent questionnaire was brought home. Three structural equation models were tested based on measures of screen time and parental style of communication from the pre-test questionnaires. Of the 152 schools invited, 62 (41 %) schools agreed to participate. In total 3325 children (average age 11.2 years and 51 % girls) and 3038 parents (81 % mothers) completed the pre-test questionnaire. The average TV/DVD times across the countries were between 1.5 and 1.8 h/day, while less time was used for computer/games console (0.9-1.4 h/day). The children's perceived parental style of communication was quite consistent for TV/DVD and computer/games console. The presence of rules was significantly associated with less time watching TV/DVD and use of computer/games console time. Moreover, the use of an autonomy-supportive style was negatively related to both time watching TV/DVD and use of computer/games console time. The use of a controlling style was related positively to perceived excessive time used on TV/DVD and excessive time used on computer/games console. With a few exceptions, results were similar across the five countries. This study suggests that an autonomy-supportive style of communicating rules for TV/DVD or computer/ games console use is negatively related to children's time watching TV/DVD and use of computer/games console time. In contrast, a controlling style is associated with more screen time and with more perceived excessive screen time in particular. Longitudinal research is needed to further examine effects of parental style of communication on children's screen time as well as possible reciprocal effects. International Standard Randomized Controlled Trial Number Register, registration number: ISRCTN34562078 . Date applied29/07/2011, Date assigned11/10/2011.

  5. Prevalence of excessive screen time and associated factors in adolescents

    PubMed Central

    de Lucena, Joana Marcela Sales; Cheng, Luanna Alexandra; Cavalcante, Thaísa Leite Mafaldo; da Silva, Vanessa Araújo; de Farias, José Cazuza

    2015-01-01

    Objective: To determine the prevalence of excessive screen time and to analyze associated factors among adolescents. Methods: This was a cross-sectional school-based epidemiological study with 2874 high school adolescents with age 14-19 years (57.8% female) from public and private schools in the city of João Pessoa, PB, Northeast Brazil. Excessive screen time was defined as watching television and playing video games or using the computer for more than 2 h/day. The associated factors analyzed were: sociodemographic (gender, age, economic class, and skin color), physical activity and nutritional status of adolescents. Results: The prevalence of excessive screen time was 79.5% (95%CI 78.1-81.1) and it was higher in males (84.3%) compared to females (76.1%; p<0.001). In multivariate analysis, adolescent males, those aged 14-15 year old and the highest economic class had higher chances of exposure to excessive screen time. The level of physical activity and nutritional status of adolescents were not associated with excessive screen time. Conclusions: The prevalence of excessive screen time was high and varied according to sociodemographic characteristics of adolescents. It is necessary to develop interventions to reduce the excessive screen time among adolescents, particularly in subgroups with higher exposure. PMID:26298661

  6. SCS-CN based time-distributed sediment yield model

    NASA Astrophysics Data System (ADS)

    Tyagi, J. V.; Mishra, S. K.; Singh, Ranvir; Singh, V. P.

    2008-05-01

    SummaryA sediment yield model is developed to estimate the temporal rates of sediment yield from rainfall events on natural watersheds. The model utilizes the SCS-CN based infiltration model for computation of rainfall-excess rate, and the SCS-CN-inspired proportionality concept for computation of sediment-excess. For computation of sedimentographs, the sediment-excess is routed to the watershed outlet using a single linear reservoir technique. Analytical development of the model shows the ratio of the potential maximum erosion (A) to the potential maximum retention (S) of the SCS-CN method is constant for a watershed. The model is calibrated and validated on a number of events using the data of seven watersheds from India and the USA. Representative values of the A/S ratio computed for the watersheds from calibration are used for the validation of the model. The encouraging results of the proposed simple four parameter model exhibit its potential in field application.

  7. 26 CFR 1.9001-4 - Adjustments required in computing excess-profits credit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Adjustments required in computing excess... Adjustments required in computing excess-profits credit. (a) In general. Subsection (f) of the Act provides adjustments required to be made in computing the excess-profits credit for any taxable year under the Excess...

  8. [Prevalence of excessive screen time and associated factors in adolescents].

    PubMed

    de Lucena, Joana Marcela Sales; Cheng, Luanna Alexandra; Cavalcante, Thaísa Leite Mafaldo; da Silva, Vanessa Araújo; de Farias Júnior, José Cazuza

    2015-12-01

    To determine the prevalence of excessive screen time and to analyze associated factors among adolescents. This was a cross-sectional school-based epidemiological study with 2,874 high school adolescents with age 14-19 years (57.8% female) from public and private schools in the city of João Pessoa, PB, Northeast Brazil. Excessive screen time was defined as watching television and playing video games or using the computer for more than two hours per day. The associated factors analyzed were: sociodemographic (gender, age, economic class, and skin color), physical activity and nutritional status of adolescents. The prevalence of excessive screen time was 79.5% (95%CI: 78.1-81.1) and it was higher in males (84.3%) compared to females (76.1%; p<0,001). In multivariate analysis, adolescent males, aged 14-15 years old, of higher economic classes had higher chances of exposure to excessive screen time. The level of physical activity and nutritional status of adolescents were not associated with excessive screen time. The prevalence of excessive screen time was high and varied according to sociodemographic characteristics of adolescents. It is necessary to develop interventions to reduce the excessive screen time among adolescents, particularly in subgroups with higher exposure. Copyright © 2015 Sociedade de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

  9. A method for estimating peak and time of peak streamflow from excess rainfall for 10- to 640-acre watersheds in the Houston, Texas, metropolitan area

    USGS Publications Warehouse

    Asquith, William H.; Cleveland, Theodore G.; Roussel, Meghan C.

    2011-01-01

    Estimates of peak and time of peak streamflow for small watersheds (less than about 640 acres) in a suburban to urban, low-slope setting are needed for drainage design that is cost-effective and risk-mitigated. During 2007-10, the U.S. Geological Survey (USGS), in cooperation with the Harris County Flood Control District and the Texas Department of Transportation, developed a method to estimate peak and time of peak streamflow from excess rainfall for 10- to 640-acre watersheds in the Houston, Texas, metropolitan area. To develop the method, 24 watersheds in the study area with drainage areas less than about 3.5 square miles (2,240 acres) and with concomitant rainfall and runoff data were selected. The method is based on conjunctive analysis of rainfall and runoff data in the context of the unit hydrograph method and the rational method. For the unit hydrograph analysis, a gamma distribution model of unit hydrograph shape (a gamma unit hydrograph) was chosen and parameters estimated through matching of modeled peak and time of peak streamflow to observed values on a storm-by-storm basis. Watershed mean or watershed-specific values of peak and time to peak ("time to peak" is a parameter of the gamma unit hydrograph and is distinct from "time of peak") of the gamma unit hydrograph were computed. Two regression equations to estimate peak and time to peak of the gamma unit hydrograph that are based on watershed characteristics of drainage area and basin-development factor (BDF) were developed. For the rational method analysis, a lag time (time-R), volumetric runoff coefficient, and runoff coefficient were computed on a storm-by-storm basis. Watershed-specific values of these three metrics were computed. A regression equation to estimate time-R based on drainage area and BDF was developed. Overall arithmetic means of volumetric runoff coefficient (0.41 dimensionless) and runoff coefficient (0.25 dimensionless) for the 24 watersheds were used to express the rational method in terms of excess rainfall (the excess rational method). Both the unit hydrograph method and excess rational method are shown to provide similar estimates of peak and time of peak streamflow. The results from the two methods can be combined by using arithmetic means. A nomograph is provided that shows the respective relations between the arithmetic-mean peak and time of peak streamflow to drainage areas ranging from 10 to 640 acres. The nomograph also shows the respective relations for selected BDF ranging from undeveloped to fully developed conditions. The nomograph represents the peak streamflow for 1 inch of excess rainfall based on drainage area and BDF; the peak streamflow for design storms from the nomograph can be multiplied by the excess rainfall to estimate peak streamflow. Time of peak streamflow is readily obtained from the nomograph. Therefore, given excess rainfall values derived from watershed-loss models, which are beyond the scope of this report, the nomograph represents a method for estimating peak and time of peak streamflow for applicable watersheds in the Houston metropolitan area. Lastly, analysis of the relative influence of BDF on peak streamflow is provided, and the results indicate a 0:04log10 cubic feet per second change of peak streamflow per positive unit of change in BDF. This relative change can be used to adjust peak streamflow from the method or other hydrologic methods for a given BDF to other BDF values; example computations are provided.

  10. 7 CFR 226.22 - Procurement standards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., all contracts awarded by institutions in excess of $2,500 which involve the employment of mechanics or...). Under section 103 of the Act, each contractor shall be required to compute the wages of every mechanic... a rate of not less than 11/2 times the basic rate of pay for all hours worked in excess of 8 hours...

  11. [Computer game addiction: a psychopathological symptom complex in adolescence].

    PubMed

    Wölfling, Klaus; Thalemann, Ralf; Grüsser-Sinopoli, Sabine M

    2008-07-01

    Cases of excessive computer gaming are increasingly reported by practitioners in the psychiatric field. Since there is no standardized definition of this symptom complex, the aim of this study is to access excessive computer gaming in German adolescents as an addictive disorder and its potential negative consequences. Psychopathological computer gaming behavior was diagnosed by applying the adapted diagnostic criteria of substance-related-addictions as defined by the ICD-10. At the same time demographic variables, state of clinical anxiety and underlying cognitive mechanisms were analyzed. 6.3 % of the 221 participating pupils - mostly boys with a low educational background - fulfilled the diagnostic criteria of a behavioral addiction. Clinically diagnosed adolescents exhibited limited cognitive flexibility and were identified to utilize computer gaming as a mood management strategy. These results can be interpreted as a first hint for a prevalence estimation of psychopathological computer gaming in German adolescents.

  12. An investigation of several numerical procedures for time-asymptotic compressible Navier-Stokes solutions

    NASA Technical Reports Server (NTRS)

    Rudy, D. H.; Morris, D. J.; Blanchard, D. K.; Cooke, C. H.; Rubin, S. G.

    1975-01-01

    The status of an investigation of four numerical techniques for the time-dependent compressible Navier-Stokes equations is presented. Results for free shear layer calculations in the Reynolds number range from 1000 to 81000 indicate that a sequential alternating-direction implicit (ADI) finite-difference procedure requires longer computing times to reach steady state than a low-storage hopscotch finite-difference procedure. A finite-element method with cubic approximating functions was found to require excessive computer storage and computation times. A fourth method, an alternating-direction cubic spline technique which is still being tested, is also described.

  13. TV Watching and Computer Use in U.S. Youth Aged 12-15, 2012. NCHS Data Brief. Number 157

    ERIC Educational Resources Information Center

    Herrick, Kirsten A.; Fakhouri, Tala H. I.; Carlson, Susan A.; Fulton, Janet E.

    2014-01-01

    Excessive screen-time behaviors, such as using a computer and watching TV, for more than 2 hours daily have been linked with elevated blood pressure, elevated serum cholesterol, and being overweight or obese among youth. Additionally, screen-time behavior established in adolescence has been shown to track into adulthood. The National Heart, Lung,…

  14. 7 CFR 3203.4 - Procedures.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., DEPARTMENT OF AGRICULTURE GUIDELINES FOR THE TRANSFER OF EXCESS COMPUTERS OR OTHER TECHNICAL EQUIPMENT..., in writing, an authorized official to approve transfers of excess computers or other technical...) Excess computers or other technical equipment must first be internally screened to ensure it is not...

  15. 7 CFR 3203.4 - Procedures.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., DEPARTMENT OF AGRICULTURE GUIDELINES FOR THE TRANSFER OF EXCESS COMPUTERS OR OTHER TECHNICAL EQUIPMENT..., in writing, an authorized official to approve transfers of excess computers or other technical...) Excess computers or other technical equipment must first be internally screened to ensure it is not...

  16. 7 CFR 3203.9 - Accountability and recordkeeping.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... recordkeeping. (a) USDA requires all excess computers or other technical equipment received by an eligible... review the reports for accuracy, as well as fair and equitable distribution of the excess computers or... PROPERTY MANAGEMENT, DEPARTMENT OF AGRICULTURE GUIDELINES FOR THE TRANSFER OF EXCESS COMPUTERS OR OTHER...

  17. 7 CFR 3203.9 - Accountability and recordkeeping.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... recordkeeping. (a) USDA requires all excess computers or other technical equipment received by an eligible... review the reports for accuracy, as well as fair and equitable distribution of the excess computers or... PROPERTY MANAGEMENT, DEPARTMENT OF AGRICULTURE GUIDELINES FOR THE TRANSFER OF EXCESS COMPUTERS OR OTHER...

  18. WE-EF-303-10: Single- Detector Proton Radiography as a Portal Imaging Equivalent for Proton Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Doolan, P; Bentefour, E; Testa, M

    2015-06-15

    Purpose: In proton therapy, patient alignment is of critical importance due to the sensitivity of the proton range to tissue heterogeneities. Traditionally proton radiography is used for verification of the water-equivalent path length (WEPL), which dictates the depth protons reach. In this work we propose its use for alignment. Additionally, many new proton centers have cone-beam computed tomography in place of beamline X-ray imaging and so proton radiography offers a unique patient alignment verification similar to portal imaging in photon therapy. Method: Proton radiographs of a CIRS head phantom were acquired using the Beam Imaging System (BIS) (IBA, Louvain-la-Neuve) inmore » a horizontal beamline. A scattered beam was produced using a small, dedicated, range modulator (RM) wheel fabricated out of aluminum. The RM wheel was rotated slowly (20 sec/rev) using a stepper motor to compensate for the frame rate of the BIS (120 ms). Dose rate functions (DRFs) over two RM wheel rotations were acquired. Calibration was made with known thicknesses of homogeneous solid water. For each pixel the time width, skewness and kurtosis of the DRFs were computed. The time width was used to compute the object WEPL. In the heterogeneous phantom, the excess skewness and excess kurtosis (i.e. difference from homogeneous cases) were computed and assessed for suitability for patient set up. Results: The technique allowed for the simultaneous production of images that can be used for WEPL verification, showing few internal details, and excess skewness and kurtosis images that can be used for soft tissue alignment. These latter images highlight areas where range mixing has occurred, correlating with phantom heterogeneities. Conclusion: The excess skewness and kurtosis images contain details that are not visible in the WET images. These images, unique to the time-resolved proton radiographic method, could be used for patient set up according to soft tissues.« less

  19. [Excessive computer usage in adolescents--results of a psychometric evaluation].

    PubMed

    Grüsser, Sabine M; Thalemann, Ralf; Albrecht, Ulrike; Thalemann, Carolin N

    2005-03-01

    Excessive computer and video game playing among children is being critically discussed from a pedagogic and public health point of view. To date, no reliable data for this phenomenon in Germany exists. In the present study, the excessive usage of computer and video games is seen as a rewarding behavior which can, due to learning mechanisms, become a prominent and inadequate strategy for children to cope with negative emotions like frustration, uneasiness and fears. In the survey, 323 children ranging in age from 11 to 14 years were asked about their video game playing behavior. Criteria for excessive computer and video game playing were developed in accordance with the criteria for dependency and pathological gambling (DSM-IV, ICD-10). Data show that 9.3% (N = 30) of the children fulfill all criteria for excessive computer and video game playing. Furthermore, these children differ from their class mates with respect to watching television, communication patterns, the ability to concentrate in school lectures and the preferred strategies coping with negative emotions. In accordance with findings in studies about substance-related addiction, data suggest that excessive computer and video game players use their excessive rewarding behavior specifically as an inadequate stress coping strategy.

  20. Zero side force volute development

    NASA Technical Reports Server (NTRS)

    Anderson, P. G.; Franz, R. J.; Farmer, R. C.; Chen, Y. S.

    1995-01-01

    Collector scrolls on high performance centrifugal pumps are currently designed with methods which are based on very approximate flowfield models. Such design practices result in some volute configurations causing excessive side loads even at design flowrates. The purpose of this study was to develop and verify computational design tools which may be used to optimize volute configurations with respect to avoiding excessive loads on the bearings. The new design methodology consisted of a volute grid generation module and a computational fluid dynamics (CFD) module to describe the volute geometry and predict the radial forces for a given flow condition, respectively. Initially, the CFD module was used to predict the impeller and the volute flowfields simultaneously; however, the required computation time was found to be excessive for parametric design studies. A second computational procedure was developed which utilized an analytical impeller flowfield model and an ordinary differential equation to describe the impeller/volute coupling obtained from the literature, Adkins & Brennen (1988). The second procedure resulted in 20 to 30 fold increase in computational speed for an analysis. The volute design analysis was validated by postulating a volute geometry, constructing a volute to this configuration, and measuring the steady radial forces over a range of flow coefficients. Excellent agreement between model predictions and observed pump operation prove the computational impeller/volute pump model to be a valuable design tool. Further applications are recommended to fully establish the benefits of this new methodology.

  1. 5 CFR 630.202 - Full biweekly pay period; leave earnings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    .... (b) Part-time employees. Hours in a pay status in excess of an agency's basic working hours in a pay period are disregarded in computing the leave earnings of a part-time employee. [33 FR 12475, Sept. 4... biweekly pay period; leave earnings. (a) Full-time employees. A full-time employee earns leave during each...

  2. Calculation of the twilight visibility function of near-sun objects

    NASA Technical Reports Server (NTRS)

    Kastner, S. O.

    1976-01-01

    The visibility function, defined here as the magnitude difference between the excess brightness of a given object and that of the background sky, of near-sun objects during twilight is obtained from a general calculation which considers the twilight sky background, atmospheric extinction, and night glow. Visibility curves are computed for a number of cases in which observations have been recorded, particularly that of comet Kohoutek. For this object, the computed visibility maxima agree well in time with the reported times of observation.

  3. Prediction of mesothelioma and lung cancer in a cohort of asbestos exposed workers.

    PubMed

    Gasparrini, Antonio; Pizzo, Anna Maria; Gorini, Giuseppe; Seniori Costantini, Adele; Silvestri, Stefano; Ciapini, Cesare; Innocenti, Andrea; Berry, Geoffrey

    2008-01-01

    Several papers have reported state-wide projections of mesothelioma deaths, but few have computed these predictions in selected exposed groups. To predict the future deaths attributable to asbestos in a cohort of railway rolling stock workers. The future mortality of the 1,146 living workers has been computed in term of individual probability of dying for three different risks: baseline mortality, lung cancer excess, mesothelioma mortality. Lung cancer mortality attributable to asbestos was calculated assuming the excess risk as stable or with a decrease after a period of time since first exposure. Mesothelioma mortality was based on cumulative exposure and time since first exposure, with the inclusion of a term for clearance of asbestos fibres from the lung. The most likely range of the number of deaths attributable to asbestos in the period 2005-2050 was 15-30 for excess of lung cancer, and 23-35 for mesothelioma. This study provides predictions of asbestos-related mortality even in a selected cohort of exposed subjects, using previous knowledge about exposure-response relationship. The inclusion of individual information in the projection model helps reduce misclassification and improves the results. The method could be extended in other selected cohorts.

  4. Protons in non-ionic aqueous reverse micelles.

    PubMed

    Rodriguez, Javier; Martí, Jordi; Guàrdia, Elvira; Laria, Daniel

    2007-05-03

    Using molecular dynamics techniques, we investigate the solvation of an excess proton within an aqueous reverse micelle in vacuo, with the neutral surfactant diethylene glycol monodecyl ether [CH3(CH2)11(OC2H4)2OH]. The simulation experiments were performed using a multistate empirical valence bond Hamiltonian model. Our results show that the stable solvation environments for the excess proton are located in the water-surfactant interface and that its first solvation shell is composed exclusively by water molecules. The relative prevalence of Eigen- versus Zundel-like solvation structures is investigated; compared to bulk results, Zundel-like structures in micelles become somewhat more stable. Characteristic times for the proton translocation jumps have been computed using population relaxation time correlation functions. The micellar rate for proton transfer is approximately 40x smaller than that found in bulk water at ambient conditions. Differences in the computed rates are examined in terms of the hydrogen-bond connectivity involving the first solvation shell of the excess charge with the rest of the micellar environment. Simulation results would indicate that proton transfers are correlated with rare episodes during which the HB connectivity between the first and second solvation shells suffers profound modifications.

  5. Event-based estimation of water budget components using the network of multi-sensor capacitance probes

    USDA-ARS?s Scientific Manuscript database

    A time-scale-free approach was developed for estimation of water fluxes at boundaries of monitoring soil profile using water content time series. The approach uses the soil water budget to compute soil water budget components, i.e. surface-water excess (Sw), infiltration less evapotranspiration (I-E...

  6. Supercomputer requirements for selected disciplines important to aerospace

    NASA Technical Reports Server (NTRS)

    Peterson, Victor L.; Kim, John; Holst, Terry L.; Deiwert, George S.; Cooper, David M.; Watson, Andrew B.; Bailey, F. Ron

    1989-01-01

    Speed and memory requirements placed on supercomputers by five different disciplines important to aerospace are discussed and compared with the capabilities of various existing computers and those projected to be available before the end of this century. The disciplines chosen for consideration are turbulence physics, aerodynamics, aerothermodynamics, chemistry, and human vision modeling. Example results for problems illustrative of those currently being solved in each of the disciplines are presented and discussed. Limitations imposed on physical modeling and geometrical complexity by the need to obtain solutions in practical amounts of time are identified. Computational challenges for the future, for which either some or all of the current limitations are removed, are described. Meeting some of the challenges will require computer speeds in excess of exaflop/s (10 to the 18th flop/s) and memories in excess of petawords (10 to the 15th words).

  7. Relationship of weight status, physical activity and screen time with academic achievement in adolescents.

    PubMed

    García-Hermoso, Antonio; Marina, Raquel

    The aim of this study was to examine the relationship of weight status, physical activity and screen time with academic achievement in Chilean adolescents. The present cross-sectional study included 395 adolescents. The International Obesity Task Force cut-off points were used to define the weight status. Physical activity was assessed using the Physical Activity Questionnaire for Adolescents and screen time was assessed using several questions about television, videogame and computer use. Academic achievement was measured using the mean of the grades obtained in mathematics and language subjects. In both genders, adolescents with obesity and excessive screen time earned worse grades compared to their non-obese peers and their peers that complied with screen time recommendations. The logistic regression analysis showed that adolescents with obesity, classified with medium-low physical activity and excessive screen time recommendations (excess ≥2h/day) are less likely to obtain high academic achievement (boys: OR=0.26; girls: OR=0.23) compared to their non-obese peers, high levels of physical activity and those who comply with the current screen time recommendations. Similar results were observed in adolescents with obesity and classified with medium-low physical activity (boys: OR=0.46; girls: OR=0.33) or excessive screen time (boys: OR=0.35; girls: OR=0.36) compared to adolescents with high levels of physical activity and those who complied with the screen time recommendations, respectively. This study shows that when combined, obesity, low-medium levels of physical activity and excessive screen time might be related to poor academic achievement. Copyright © 2015 Asia Oceania Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.

  8. [Nutritional status and screen time among public school students in Niterói, Rio de Janeiro State, Brazil].

    PubMed

    Vasconcellos, Marcelo Barros de; Anjos, Luiz Antonio dos; Vasconcellos, Mauricio Teixeira Leite de

    2013-04-01

    The aim of this study was to assess nutritional status, sedentary behavior (TV, computer, and videogame time and screen time as the sum of these first three) and physical activity using a questionnaire with youth (10 to 18 years of age) enrolled in public schools in Niterói, Rio de Janeiro State, Brazil. Anthropometry (body mass and stature), sedentary behavior, and information on physical activity were obtained in a probability sample of 10 to 18 year-old students (n = 328; 108 boys) stratified by school and selected in two stages (classes and students). Low height for age did not appear as a problem, but 25.7% of the youth presented excess weight (18% overweight and 7.7% obese). Total screen time did not differ between the sexes, but boys spent more time playing videogames than girls, regardless of age, while girls watched more TV. Boys spent twice as much time as girls of all ages in physical activity (three times more in the ≥ 14 year-old group). Screen time was significantly associated with excess weight. In conclusion, public school youth in Niterói show high prevalence rates of excess weight associated with inadequate lifestyle.

  9. Sedentary behavior based on screen time: prevalence and associated sociodemographic factors in adolescents.

    PubMed

    Sousa, Gabriel Renaldo de; Silva, Diego Augusto Santos

    2017-12-01

    The aim of this study to estimate the prevalence of sedentary behavior based on screen time (≥ 2-hour day) and to identify the association with sociodemographic factors among adolescents in a city in southern Brazil. This is an epidemiological survey of school-based cross-sectional study with students aged 14-19 years in the city of São José/SC - Brazil. Self-administered questionnaire was used, containing information sociodemographic, level of physical activity and about screen time. Descriptive statistics were performed, and odds ratios were estimated using binary logistic regression and 95% confidence level. The prevalence of excess screen time was 86.37% followed by computer use (55.24%), TV use (51.56%) and Videogame use (15.35%). Boys had higher prevalence of excessive video game use. Those of skin color different from white and mothers who studied less than eight years were more likely to watch too much TV, and those of low economic level were more likely of having excessive screen time. Girls of skin color different from white were more likely to watch too much TV, and those aged 14-16 years were more likely to have videogame use time and total time screen above recommended.

  10. Excessive computer game playing among Norwegian adults: self-reported consequences of playing and association with mental health problems.

    PubMed

    Wenzel, H G; Bakken, I J; Johansson, A; Götestam, K G; Øren, Anita

    2009-12-01

    Computer games are the most advanced form of gaming. For most people, the playing is an uncomplicated leisure activity; however, for a minority the gaming becomes excessive and is associated with negative consequences. The aim of the present study was to investigate computer game-playing behaviour in the general adult Norwegian population, and to explore mental health problems and self-reported consequences of playing. The survey includes 3,405 adults 16 to 74 years old (Norway 2007, response rate 35.3%). Overall, 65.5% of the respondents reported having ever played computer games (16-29 years, 93.9%; 30-39 years, 85.0%; 40-59 years, 56.2%; 60-74 years, 25.7%). Among 2,170 players, 89.8% reported playing less than 1 hr. as a daily average over the last month, 5.0% played 1-2 hr. daily, 3.1% played 2-4 hr. daily, and 2.2% reported playing > 4 hr. daily. The strongest risk factor for playing > 4 hr. daily was being an online player, followed by male gender, and single marital status. Reported negative consequences of computer game playing increased strongly with average daily playing time. Furthermore, prevalence of self-reported sleeping problems, depression, suicide ideations, anxiety, obsessions/ compulsions, and alcohol/substance abuse increased with increasing playing time. This study showed that adult populations should also be included in research on computer game-playing behaviour and its consequences.

  11. Computer analysis of railcar vibrations

    NASA Technical Reports Server (NTRS)

    Vlaminck, R. R.

    1975-01-01

    Computer models and techniques for calculating railcar vibrations are discussed along with criteria for vehicle ride optimization. The effect on vibration of car body structural dynamics, suspension system parameters, vehicle geometry, and wheel and rail excitation are presented. Ride quality vibration data collected on the state-of-the-art car and standard light rail vehicle is compared to computer predictions. The results show that computer analysis of the vehicle can be performed for relatively low cost in short periods of time. The analysis permits optimization of the design as it progresses and minimizes the possibility of excessive vibration on production vehicles.

  12. Dissipation in adiabatic quantum computers: lessons from an exactly solvable model

    NASA Astrophysics Data System (ADS)

    Keck, Maximilian; Montangero, Simone; Santoro, Giuseppe E.; Fazio, Rosario; Rossini, Davide

    2017-11-01

    We introduce and study the adiabatic dynamics of free-fermion models subject to a local Lindblad bath and in the presence of a time-dependent Hamiltonian. The merit of these models is that they can be solved exactly, and will help us to study the interplay between nonadiabatic transitions and dissipation in many-body quantum systems. After the adiabatic evolution, we evaluate the excess energy (the average value of the Hamiltonian) as a measure of the deviation from reaching the final target ground state. We compute the excess energy in a variety of different situations, where the nature of the bath and the Hamiltonian is modified. We find robust evidence of the fact that an optimal working time for the quantum annealing protocol emerges as a result of the competition between the nonadiabatic effects and the dissipative processes. We compare these results with the matrix-product-operator simulations of an Ising system and show that the phenomenology we found also applies for this more realistic case.

  13. Everything in Moderation: Moderate Use of Screens Unassociated with Child Behavior Problems.

    PubMed

    Ferguson, Christopher J

    2017-12-01

    The impact of children's use of "screen" media including television and computer games, continues to be debated. The American Academy of Pediatrics (AAP) until recently recommended a relatively restrictive screen time diet of 2 h or less for most youth. A representative correlational sample of youth were assessed for links between screen time and risky behavioral outcomes. Data collection occurred in 2013 conducted by the State of Florida. Use of screens that was moderately high, in excess of the AAP's former recommendations, but not excessive (1 SD or higher than average), was not associated with delinquency, risky behaviors, sexual behaviors, substance abuse, reduced grades or mental health problems. Even excessive screen use (1 SD or higher) was only weakly associated with negative outcomes related to delinquency, grades and depression only, and at levels unlikely to be practically significant. Results conceptually replicate those of Przybylski (2014) with a US sample for depression and delinquency as outcomes. Moderate use of screens, though in excess of the AAP's historical recommendations, are unassociated with problem outcomes. Excessive use of screens is only weakly associated with negative outcomes, and only those related to depression and delinquency as well as reduced grades, but not risky driving, substance use, risky sex or disordered eating. Although an "everything in moderation" message when discussing screen time with parents may be most productive, results do not support a strong focus on screen time as a preventative measure for youth problem behaviors.

  14. SENSITIVITY OF HELIOSEISMIC TRAVEL TIMES TO THE IMPOSITION OF A LORENTZ FORCE LIMITER IN COMPUTATIONAL HELIOSEISMOLOGY

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moradi, Hamed; Cally, Paul S., E-mail: hamed.moradi@monash.edu

    The rapid exponential increase in the Alfvén wave speed with height above the solar surface presents a serious challenge to physical modeling of the effects of magnetic fields on solar oscillations, as it introduces a significant Courant-Friedrichs-Lewy time-step constraint for explicit numerical codes. A common approach adopted in computational helioseismology, where long simulations in excess of 10 hr (hundreds of wave periods) are often required, is to cap the Alfvén wave speed by artificially modifying the momentum equation when the ratio between the Lorentz and hydrodynamic forces becomes too large. However, recent studies have demonstrated that the Alfvén wave speedmore » plays a critical role in the MHD mode conversion process, particularly in determining the reflection height of the upwardly propagating helioseismic fast wave. Using numerical simulations of helioseismic wave propagation in constant inclined (relative to the vertical) magnetic fields we demonstrate that the imposition of such artificial limiters significantly affects time-distance travel times unless the Alfvén wave-speed cap is chosen comfortably in excess of the horizontal phase speeds under investigation.« less

  15. Excessive computer game playing: evidence for addiction and aggression?

    PubMed

    Grüsser, S M; Thalemann, R; Griffiths, M D

    2007-04-01

    Computer games have become an ever-increasing part of many adolescents' day-to-day lives. Coupled with this phenomenon, reports of excessive gaming (computer game playing) denominated as "computer/video game addiction" have been discussed in the popular press as well as in recent scientific research. The aim of the present study was the investigation of the addictive potential of gaming as well as the relationship between excessive gaming and aggressive attitudes and behavior. A sample comprising of 7069 gamers answered two questionnaires online. Data revealed that 11.9% of participants (840 gamers) fulfilled diagnostic criteria of addiction concerning their gaming behavior, while there is only weak evidence for the assumption that aggressive behavior is interrelated with excessive gaming in general. Results of this study contribute to the assumption that also playing games without monetary reward meets criteria of addiction. Hence, an addictive potential of gaming should be taken into consideration regarding prevention and intervention.

  16. Structural performance analysis and redesign

    NASA Technical Reports Server (NTRS)

    Whetstone, W. D.

    1978-01-01

    Program performs stress buckling and vibrational analysis of large, linear, finite-element systems in excess of 50,000 degrees of freedom. Cost, execution time, and storage requirements are kept reasonable through use of sparse matrix solution techniques, and other computational and data management procedures designed for problems of very large size.

  17. 26 CFR 1.860E-2 - Tax on transfers of residual interests to certain organizations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... excess inclusions. The anticipated excess inclusions are the excess inclusions that are expected to... anticipated excess inclusions must be determined as of the date the residual interest is transferred and must...) Present value computation. The present value of the anticipated excess inclusions is determined by...

  18. Algorithm implementation on the Navier-Stokes computer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krist, S.E.; Zang, T.A.

    1987-03-01

    The Navier-Stokes Computer is a multi-purpose parallel-processing supercomputer which is currently under development at Princeton University. It consists of multiple local memory parallel processors, called Nodes, which are interconnected in a hypercube network. Details of the procedures involved in implementing an algorithm on the Navier-Stokes computer are presented. The particular finite difference algorithm considered in this analysis was developed for simulation of laminar-turbulent transition in wall bounded shear flows. Projected timing results for implementing this algorithm indicate that operation rates in excess of 42 GFLOPS are feasible on a 128 Node machine.

  19. Algorithm implementation on the Navier-Stokes computer

    NASA Technical Reports Server (NTRS)

    Krist, Steven E.; Zang, Thomas A.

    1987-01-01

    The Navier-Stokes Computer is a multi-purpose parallel-processing supercomputer which is currently under development at Princeton University. It consists of multiple local memory parallel processors, called Nodes, which are interconnected in a hypercube network. Details of the procedures involved in implementing an algorithm on the Navier-Stokes computer are presented. The particular finite difference algorithm considered in this analysis was developed for simulation of laminar-turbulent transition in wall bounded shear flows. Projected timing results for implementing this algorithm indicate that operation rates in excess of 42 GFLOPS are feasible on a 128 Node machine.

  20. Impact of singular excessive computer game and television exposure on sleep patterns and memory performance of school-aged children.

    PubMed

    Dworak, Markus; Schierl, Thomas; Bruns, Thomas; Strüder, Heiko Klaus

    2007-11-01

    Television and computer game consumption are a powerful influence in the lives of most children. Previous evidence has supported the notion that media exposure could impair a variety of behavioral characteristics. Excessive television viewing and computer game playing have been associated with many psychiatric symptoms, especially emotional and behavioral symptoms, somatic complaints, attention problems such as hyperactivity, and family interaction problems. Nevertheless, there is insufficient knowledge about the relationship between singular excessive media consumption on sleep patterns and linked implications on children. The aim of this study was to investigate the effects of singular excessive television and computer game consumption on sleep patterns and memory performance of children. Eleven school-aged children were recruited for this polysomnographic study. Children were exposed to voluntary excessive television and computer game consumption. In the subsequent night, polysomnographic measurements were conducted to measure sleep-architecture and sleep-continuity parameters. In addition, a visual and verbal memory test was conducted before media stimulation and after the subsequent sleeping period to determine visuospatial and verbal memory performance. Only computer game playing resulted in significant reduced amounts of slow-wave sleep as well as significant declines in verbal memory performance. Prolonged sleep-onset latency and more stage 2 sleep were also detected after previous computer game consumption. No effects on rapid eye movement sleep were observed. Television viewing reduced sleep efficiency significantly but did not affect sleep patterns. The results suggest that television and computer game exposure affect children's sleep and deteriorate verbal cognitive performance, which supports the hypothesis of the negative influence of media consumption on children's sleep, learning, and memory.

  1. Parallel image reconstruction for 3D positron emission tomography from incomplete 2D projection data

    NASA Astrophysics Data System (ADS)

    Guerrero, Thomas M.; Ricci, Anthony R.; Dahlbom, Magnus; Cherry, Simon R.; Hoffman, Edward T.

    1993-07-01

    The problem of excessive computational time in 3D Positron Emission Tomography (3D PET) reconstruction is defined, and we present an approach for solving this problem through the construction of an inexpensive parallel processing system and the adoption of the FAVOR algorithm. Currently, the 3D reconstruction of the 610 images of a total body procedure would require 80 hours and the 3D reconstruction of the 620 images of a dynamic study would require 110 hours. An inexpensive parallel processing system for 3D PET reconstruction is constructed from the integration of board level products from multiple vendors. The system achieves its computational performance through the use of 6U VME four i860 processor boards, the processor boards from five manufacturers are discussed from our perspective. The new 3D PET reconstruction algorithm FAVOR, FAst VOlume Reconstructor, that promises a substantial speed improvement is adopted. Preliminary results from parallelizing FAVOR are utilized in formulating architectural improvements for this problem. In summary, we are addressing the problem of excessive computational time in 3D PET image reconstruction, through the construction of an inexpensive parallel processing system and the parallelization of a 3D reconstruction algorithm that uses the incomplete data set that is produced by current PET systems.

  2. Computer/gaming station use in youth: Correlations among use, addiction and functional impairment

    PubMed Central

    Baer, Susan; Saran, Kelly; Green, David A

    2012-01-01

    OBJECTIVE: Computer/gaming station use is ubiquitous in the lives of youth today. Overuse is a concern, but it remains unclear whether problems arise from addictive patterns of use or simply excessive time spent on use. The goal of the present study was to evaluate computer/gaming station use in youth and to examine the relationship between amounts of use, addictive features of use and functional impairment. METHOD: A total of 110 subjects (11 to 17 years of age) from local schools participated. Time spent on television, video gaming and non-gaming recreational computer activities was measured. Addictive features of computer/gaming station use were ascertained, along with emotional/behavioural functioning. Multiple linear regressions were used to understand how youth functioning varied with time of use and addictive features of use. RESULTS: Mean (± SD) total screen time was 4.5±2.4 h/day. Addictive features of use were consistently correlated with functional impairment across multiple measures and informants, whereas time of use, after controlling for addiction, was not. CONCLUSIONS: Youth are spending many hours each day in front of screens. In the absence of addictive features of computer/gaming station use, time spent is not correlated with problems; however, youth with addictive features of use show evidence of poor emotional/ behavioural functioning. PMID:24082802

  3. Solving magnetostatic field problems with NASTRAN

    NASA Technical Reports Server (NTRS)

    Hurwitz, M. M.; Schroeder, E. A.

    1978-01-01

    Determining the three-dimensional magnetostatic field in current-induced situations has usually involved vector potentials, which can lead to excessive computational times. How such magnetic fields may be determined using scalar potentials is reviewed. It is shown how the heat transfer capability of NASTRAN level 17 was modified to take advantage of the new method.

  4. Childhood Obesity: A Growing Phenomenon for Physical Educators

    ERIC Educational Resources Information Center

    Green, Gregory; Reese, Shirley A.

    2006-01-01

    The greatest health risk facing children today is obesity. The prevalence of childhood obesity in the United States has risen dramatically in the past several decades. Because children on the average spend up to five or six hours a day involved in sedentary activities, including excessive time watching television, using the computer and playing…

  5. Application of two direct runoff prediction methods in Puerto Rico

    USGS Publications Warehouse

    Sepulveda, N.

    1997-01-01

    Two methods for predicting direct runoff from rainfall data were applied to several basins and the resulting hydrographs compared to measured values. The first method uses a geomorphology-based unit hydrograph to predict direct runoff through its convolution with the excess rainfall hyetograph. The second method shows how the resulting hydraulic routing flow equation from a kinematic wave approximation is solved using a spectral method based on the matrix representation of the spatial derivative with Chebyshev collocation and a fourth-order Runge-Kutta time discretization scheme. The calibrated Green-Ampt (GA) infiltration parameters are obtained by minimizing the sum, over several rainfall events, of absolute differences between the total excess rainfall volume computed from the GA equations and the total direct runoff volume computed from a hydrograph separation technique. The improvement made in predicting direct runoff using a geomorphology-based unit hydrograph with the ephemeral and perennial stream network instead of the strictly perennial stream network is negligible. The hydraulic routing scheme presented here is highly accurate in predicting the magnitude and time of the hydrograph peak although the much faster unit hydrograph method also yields reasonable results.

  6. Time-Accurate Simulations and Acoustic Analysis of Slat Free-Shear-Layer. Part 2

    NASA Technical Reports Server (NTRS)

    Khorrami, Mehdi R.; Singer, Bart A.; Lockard, David P.

    2002-01-01

    Unsteady computational simulations of a multi-element, high-lift configuration are performed. Emphasis is placed on accurate spatiotemporal resolution of the free shear layer in the slat-cove region. The excessive dissipative effects of the turbulence model, so prevalent in previous simulations, are circumvented by switching off the turbulence-production term in the slat cove region. The justifications and physical arguments for taking such a step are explained in detail. The removal of this excess damping allows the shear layer to amplify large-scale structures, to achieve a proper non-linear saturation state, and to permit vortex merging. The large-scale disturbances are self-excited, and unlike our prior fully turbulent simulations, no external forcing of the shear layer is required. To obtain the farfield acoustics, the Ffowcs Williams and Hawkings equation is evaluated numerically using the simulated time-accurate flow data. The present comparison between the computed and measured farfield acoustic spectra shows much better agreement for the amplitude and frequency content than past calculations. The effect of the angle-of-attack on the slat's flow features radiated acoustic field are also simulated presented.

  7. Television viewing, computer use and total screen time in Canadian youth.

    PubMed

    Mark, Amy E; Boyce, William F; Janssen, Ian

    2006-11-01

    Research has linked excessive television viewing and computer use in children and adolescents to a variety of health and social problems. Current recommendations are that screen time in children and adolescents should be limited to no more than 2 h per day. To determine the percentage of Canadian youth meeting the screen time guideline recommendations. The representative study sample consisted of 6942 Canadian youth in grades 6 to 10 who participated in the 2001/2002 World Health Organization Health Behaviour in School-Aged Children survey. Only 41% of girls and 34% of boys in grades 6 to 10 watched 2 h or less of television per day. Once the time of leisure computer use was included and total daily screen time was examined, only 18% of girls and 14% of boys met the guidelines. The prevalence of those meeting the screen time guidelines was higher in girls than boys. Fewer than 20% of Canadian youth in grades 6 to 10 met the total screen time guidelines, suggesting that increased public health interventions are needed to reduce the number of leisure time hours that Canadian youth spend watching television and using the computer.

  8. Prevalence of headache in adolescents and association with use of computer and videogames.

    PubMed

    Xavier, Michelle Katherine Andrade; Pitangui, Ana Carolina Rodarti; Silva, Georgia Rodrigues Reis; Oliveira, Valéria Mayaly Alves de; Beltrão, Natália Barros; Araújo, Rodrigo Cappato de

    2015-11-01

    The aim of this study was to determine the prevalence of headache in adolescents and its association with excessive use of electronic devices and games. The sample comprised 954 adolescents of both sexes (14 to 19 years) who answered a questionnaire about use of computers and electronic games, presence of headache and physical activity. The binary and multinomial logistic regression, with significance level of 5% was used for inferential analysis. The prevalence of headache was 80.6%. The excessive use of electronics devices proved to be a risk factor (OR = 1.21) for headache. Subjects aged between 14 and 16 years were less likely to report headache (OR = 0.64). Regarding classification, 17.9% of adolescents had tension-type headache, 19.3% had migraine and 43.4% other types of headache. The adolescents aged form 14 to 16 years had lower chance (OR ≤ 0.68) to report the tension-type headache and other types of headache. The excessive use of digital equipment, electronic games and attending the third year of high school proved to be risk factors for migraine-type development (OR ≥ 1.84). There was a high prevalence of headache in adolescents and high-time use of electronic devices. We observed an association between excessive use of electronic devices and the presence of headache, and this habit is considered a risk factor, especially for the development of migraine-type.

  9. Biological and statistical approaches to predicting human lung cancer risk from silica.

    PubMed

    Kuempel, E D; Tran, C L; Bailer, A J; Porter, D W; Hubbs, A F; Castranova, V

    2001-01-01

    Chronic inflammation is a key step in the pathogenesis of particle-elicited fibrosis and lung cancer in rats, and possibly in humans. In this study, we compute the excess risk estimates for lung cancer in humans with occupational exposure to crystalline silica, using both rat and human data, and using both a threshold approach and linear models. From a toxicokinetic/dynamic model fit to lung burden and pulmonary response data from a subchronic inhalation study in rats, we estimated the minimum critical quartz lung burden (Mcrit) associated with reduced pulmonary clearance and increased neutrophilic inflammation. A chronic study in rats was also used to predict the human excess risk of lung cancer at various quartz burdens, including mean Mcrit (0.39 mg/g lung). We used a human kinetic lung model to link the equivalent lung burdens to external exposures in humans. We then computed the excess risk of lung cancer at these external exposures, using data of workers exposed to respirable crystalline silica and using Poisson regression and lifetable analyses. Finally, we compared the lung cancer excess risks estimated from male rat and human data. We found that the rat-based linear model estimates were approximately three times higher than those based on human data (e.g., 2.8% in rats vs. 0.9-1% in humans, at mean Mcrit lung burden or associated mean working lifetime exposure of 0.036 mg/m3). Accounting for variability and uncertainty resulted in 100-1000 times lower estimates of human critical lung burden and airborne exposure. This study illustrates that assumptions about the relevant biological mechanism, animal model, and statistical approach can all influence the magnitude of lung cancer risk estimates in humans exposed to crystalline silica.

  10. 76 FR 28188 - Office of Procurement and Property Management; Guidelines for the Transfer of Excess Computers or...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-16

    ... general, to provide the public the option of submitting information or transacting business electronically... Office of Procurement and Property Management; Guidelines for the Transfer of Excess Computers or Other... Property Management, USDA. ACTION: Proposed rule. SUMMARY: The Office of Procurement and Property...

  11. Insufficient Sleep Is Associated with Obesity and Excessive Screen Time Amongst Ten-Year-Old Children in Sweden.

    PubMed

    Garmy, Pernilla; Clausson, Eva K; Nyberg, Per; Jakobsson, Ulf

    This study investigated sleep, television, computer habits, and obesity in school-age children. This was a cross-sectional self-report survey of 1260 children in grade 4 (mean age, 10.1) living in southern Sweden (49.1% boys). The heights and weights of 1097 (87.1%) of the children were recorded. Descriptive statistics, bivariate analyses, and multiple logistic regression were employed. The median length of self-reported sleep on weeknights was 9.5h. Approximately 40% of the children reported receiving <9h of sleep. The median bedtime was 9PM (21:00). On weekends, the median bedtime was 1 h later, and they delayed getting up by 1.5h. The median time spent watching TV and using a computer was 1 h each. The prevalence of being overweight (including obesity) was 18%. Insufficient sleep (<9h) was associated with being overweight, watching TV, or using a computer for two or more hours each day, difficulty falling asleep, and being tired at school. School-age children who receive less sleep are more likely to be overweight and report excessive television and computer use. A strong and urgent need exists to highlight the importance of healthy sleep and media habits. It is challenging for pediatric nurses and school nurses to teach children and their families about healthy sleep and media habits. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Persistence time of charge carriers in defect states of molecular semiconductors.

    PubMed

    McMahon, David P; Troisi, Alessandro

    2011-06-07

    Charge carriers in organic crystals are often trapped in point defects. The persistence time of the charge in these defect states is evaluated by computing the escape rate from this state using non-adiabatic rate theory. Two cases are considered (i) the hopping between separate identical defect states and (ii) the hopping between a defect state and the bulk (delocalized) states. We show that only the second process is likely to happen with realistic defect concentrations and highlight that the inclusion of an effective quantum mode of vibration is essential for accurate computation of the rate. The computed persistence time as a function of the trap energy indicates that trap states shallower than ∼0.3 eV cannot be effectively investigated with some slow spectroscopic techniques such as THz spectroscopy or EPR commonly used to study the nature of excess charge in semiconductors.

  13. Coquina Elementary students enjoy gift of computers

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Children at Coquina Elementary School, Titusville, Fla., 'practice' using a computer keyboard, part of equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

  14. Coquina Elementary students enjoy gift of computers

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Children at Coquina Elementary School, Titusville, Fla., look with curiosity at the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

  15. Audubon Elementary students enjoy gift of computers

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Children at Audubon Elementary School, Merritt Island, Fla., eagerly unwrap computer equipment donated by Kennedy Space Center. Audubon is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year- long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

  16. Coquina Elementary students enjoy gift of computers

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Children at Coquina Elementary School, Titusville, Fla., eagerly tear into the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year- long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

  17. Coquina Elementary students enjoy gift of computers

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Children at Coquina Elementary School, Titusville, Fla., excitedly tear into the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

  18. KSC-99pp1227

    NASA Image and Video Library

    1999-10-06

    Children at Audubon Elementary School, Merritt Island, Fla., eagerly unwrap computer equipment donated by Kennedy Space Center. Audubon is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

  19. Robust shot-noise measurement for continuous-variable quantum key distribution

    NASA Astrophysics Data System (ADS)

    Kunz-Jacques, Sébastien; Jouguet, Paul

    2015-02-01

    We study a practical method to measure the shot noise in real time in continuous-variable quantum key distribution systems. The amount of secret key that can be extracted from the raw statistics depends strongly on this quantity since it affects in particular the computation of the excess noise (i.e., noise in excess of the shot noise) added by an eavesdropper on the quantum channel. Some powerful quantum hacking attacks relying on faking the estimated value of the shot noise to hide an intercept and resend strategy were proposed. Here, we provide experimental evidence that our method can defeat the saturation attack and the wavelength attack.

  20. A Modeling Framework for Optimal Computational Resource Allocation Estimation: Considering the Trade-offs between Physical Resolutions, Uncertainty and Computational Costs

    NASA Astrophysics Data System (ADS)

    Moslehi, M.; de Barros, F.; Rajagopal, R.

    2014-12-01

    Hydrogeological models that represent flow and transport in subsurface domains are usually large-scale with excessive computational complexity and uncertain characteristics. Uncertainty quantification for predicting flow and transport in heterogeneous formations often entails utilizing a numerical Monte Carlo framework, which repeatedly simulates the model according to a random field representing hydrogeological characteristics of the field. The physical resolution (e.g. grid resolution associated with the physical space) for the simulation is customarily chosen based on recommendations in the literature, independent of the number of Monte Carlo realizations. This practice may lead to either excessive computational burden or inaccurate solutions. We propose an optimization-based methodology that considers the trade-off between the following conflicting objectives: time associated with computational costs, statistical convergence of the model predictions and physical errors corresponding to numerical grid resolution. In this research, we optimally allocate computational resources by developing a modeling framework for the overall error based on a joint statistical and numerical analysis and optimizing the error model subject to a given computational constraint. The derived expression for the overall error explicitly takes into account the joint dependence between the discretization error of the physical space and the statistical error associated with Monte Carlo realizations. The accuracy of the proposed framework is verified in this study by applying it to several computationally extensive examples. Having this framework at hand aims hydrogeologists to achieve the optimum physical and statistical resolutions to minimize the error with a given computational budget. Moreover, the influence of the available computational resources and the geometric properties of the contaminant source zone on the optimum resolutions are investigated. We conclude that the computational cost associated with optimal allocation can be substantially reduced compared with prevalent recommendations in the literature.

  1. Reversible simulation of irreversible computation

    NASA Astrophysics Data System (ADS)

    Li, Ming; Tromp, John; Vitányi, Paul

    1998-09-01

    Computer computations are generally irreversible while the laws of physics are reversible. This mismatch is penalized by among other things generating excess thermic entropy in the computation. Computing performance has improved to the extent that efficiency degrades unless all algorithms are executed reversibly, for example by a universal reversible simulation of irreversible computations. All known reversible simulations are either space hungry or time hungry. The leanest method was proposed by Bennett and can be analyzed using a simple ‘reversible’ pebble game. The reachable reversible simulation instantaneous descriptions (pebble configurations) of such pebble games are characterized completely. As a corollary we obtain the reversible simulation by Bennett and, moreover, show that it is a space-optimal pebble game. We also introduce irreversible steps and give a theorem on the tradeoff between the number of allowed irreversible steps and the memory gain in the pebble game. In this resource-bounded setting the limited erasing needs to be performed at precise instants during the simulation. The reversible simulation can be modified so that it is applicable also when the simulated computation time is unknown.

  2. A digital approach to fabricating an abutment replica to control cement volume in a cement-retained implant prosthesis.

    PubMed

    Lee, Ju-Hyoung; Park, In-Sook; Sohn, Dong-Seok

    2016-07-01

    If a cement-retained implant prosthesis is placed on an abutment, excess cement should be minimized or removed to prevent periimplant inflammation. Various methods for fabricating an abutment replica have been introduced to maintain tissue health and reduce clean-up time. The purpose of this article is to present an alternative technique for fabricating an abutment replica with computer-aided design/computer-aided manufacturing (CAD/CAM) technology. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  3. [Computer games in childhood and adolescence: relations to addictive behavior, ADHD, and aggression].

    PubMed

    Frölich, Jan; Lehmkuhl, Gerd; Döpfner, Manfred

    2009-09-01

    Playing computer games has become one of the main leisure activities in children and adolescents and increasingly replaces traditional playing and interactional activities. There might exist developmental benefits or positive effects of computer games that can be used for educational or therapeutic purposes. More important several studies have well demonstrated that excessive computer game playing is associated with behavior that features all components of non-chemical addiction and the prevalences across all age groups seem to be impressingly high. This overview relies on a Medline research. Its objective is to describe motivational and developmental characteristics attributed to computer games as well as the prevalences of computer playing in children and adolescents to better understand the risks for addictive use. We especially focus on the relations of excessive computer playing with attention-deficit hyperactivity disorder (ADHD) and aggressive behavior. The results demonstrate that children with ADHD are especially vulnerable to addictive use of computer games due to their neuropsychological profile. Moreover excessive violent computer game playing might be a significant risk variable for aggressive behavior in the presence of personality traits with aggressive cognitions and behavior scripts in the consumers. The increasing clinical meaning of addictive computer games playing urgently necessitates the development of diagnostic and therapeutic tools for clinical practice as well as the cooperation with allied disciplines.

  4. A molecular dynamics simulation study of chloroform

    NASA Astrophysics Data System (ADS)

    Tironi, Ilario G.; van Gunsteren, Wilfred F.

    Three different chloroform models have been investigated using molecular dynamics computer simulation. The thermodynamic, structural and dynamic properties of the various models were investigated in detail. In particular, the potential energies, diffusion coefficients and rotational correlation times obtained for each model are compared with experiment. It is found that the theory of rotational Brownian motion fails in describing the rotational diffusion of chloroform. The force field of Dietz and Heinzinger was found to give good overall agreement with experiment. An extended investigation of this chloroform model has been performed. Values are reported for the isothermal compressibility, the thermal expansion coefficient and the constant volume heat capacity. The values agree well with experiment. The static and frequency dependent dielectric permittivity were computed from a 1·2 ns simulation conducted under reaction field boundary conditions. Considering the fact that the model is rigid with fixed partial charges, the static dielectric constant and Debye relaxation time compare well with experiment. From the same simulation the shear viscosity was computed using the off-diagonal elements of the pressure tensor, both via an Einstein type relation and via a Green-Kubo equation. The calculated viscosities show good agreement with experimental values. The excess Helmholtz energy is calculated using the thermodynamic integration technique and simulations of 50 and 80 ps. The value obtained for the excess Helmholtz energy matches the theoretical value within a few per cent.

  5. 26 CFR 1.383-2 - Limitations on certain capital losses and excess credits in computing alternative minimum tax...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 4 2010-04-01 2010-04-01 false Limitations on certain capital losses and excess credits in computing alternative minimum tax. [Reserved] 1.383-2 Section 1.383-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Insolvency...

  6. KSC-99pp1225

    NASA Image and Video Library

    1999-10-06

    Children at Coquina Elementary School, Titusville, Fla., excitedly tear into the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

  7. KSC-99pp1224

    NASA Image and Video Library

    1999-10-06

    Children at Coquina Elementary School, Titusville, Fla., eagerly tear into the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

  8. KSC-99pp1222

    NASA Image and Video Library

    1999-10-06

    Children at Coquina Elementary School, Titusville, Fla., look with curiosity at the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

  9. KSC-99pp1223

    NASA Image and Video Library

    1999-10-06

    Children at Coquina Elementary School, Titusville, Fla., "practice" using a computer keyboard, part of equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

  10. Development of a real-time aeroperformance analysis technique for the X-29A advanced technology demonstrator

    NASA Technical Reports Server (NTRS)

    Ray, R. J.; Hicks, J. W.; Alexander, R. I.

    1988-01-01

    The X-29A advanced technology demonstrator has shown the practicality and advantages of the capability to compute and display, in real time, aeroperformance flight results. This capability includes the calculation of the in-flight measured drag polar, lift curve, and aircraft specific excess power. From these elements many other types of aeroperformance measurements can be computed and analyzed. The technique can be used to give an immediate postmaneuver assessment of data quality and maneuver technique, thus increasing the productivity of a flight program. A key element of this new method was the concurrent development of a real-time in-flight net thrust algorithm, based on the simplified gross thrust method. This net thrust algorithm allows for the direct calculation of total aircraft drag.

  11. Control system estimation and design for aerospace vehicles with time delay

    NASA Technical Reports Server (NTRS)

    Allgaier, G. R.; Williams, T. L.

    1972-01-01

    The problems of estimation and control of discrete, linear, time-varying systems are considered. Previous solutions to these problems involved either approximate techniques, open-loop control solutions, or results which required excessive computation. The estimation problem is solved by two different methods, both of which yield the identical algorithm for determining the optimal filter. The partitioned results achieve a substantial reduction in computation time and storage requirements over the expanded solution, however. The results reduce to the Kalman filter when no delays are present in the system. The control problem is also solved by two different methods, both of which yield identical algorithms for determining the optimal control gains. The stochastic control is shown to be identical to the deterministic control, thus extending the separation principle to time delay systems. The results obtained reduce to the familiar optimal control solution when no time delays are present in the system.

  12. South Lake Elementary students enjoy gift of computers

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Nancy Nichols, principal of South Lake Elementary School, Titusville, Fla., joins students in teacher Michelle Butler's sixth grade class who are unwrapping computer equipment donated by Kennedy Space Center. South Lake is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

  13. Cambridge Elementary students enjoy gift of computers

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Children at Cambridge Elementary School, Cocoa, Fla., eagerly unwrap computer equipment donated by Kennedy Space Center. Cambridge is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. Behind the children is Jim Thurston, a school volunteer and retired employee of USBI, who shared in the project. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

  14. 48 CFR 915.404-4-71-5 - Fee schedules.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... until such Force account work exceeds, in the aggregate, 20 percent of the base. Excessive use of Force..., appropriate fee reductions for such excessive Force account labor shall be computed as follows: (1) Determine... following adjustments shall be made to the Schedule fee amounts for complexity levels, excessive...

  15. 48 CFR 915.404-4-71-5 - Fee schedules.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... until such Force account work exceeds, in the aggregate, 20 percent of the base. Excessive use of Force..., appropriate fee reductions for such excessive Force account labor shall be computed as follows: (1) Determine... following adjustments shall be made to the Schedule fee amounts for complexity levels, excessive...

  16. 48 CFR 915.404-4-71-5 - Fee schedules.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... until such Force account work exceeds, in the aggregate, 20 percent of the base. Excessive use of Force..., appropriate fee reductions for such excessive Force account labor shall be computed as follows: (1) Determine... following adjustments shall be made to the Schedule fee amounts for complexity levels, excessive...

  17. 48 CFR 915.404-4-71-5 - Fee schedules.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... until such Force account work exceeds, in the aggregate, 20 percent of the base. Excessive use of Force..., appropriate fee reductions for such excessive Force account labor shall be computed as follows: (1) Determine... following adjustments shall be made to the Schedule fee amounts for complexity levels, excessive...

  18. 48 CFR 915.404-4-71-5 - Fee schedules.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... until such Force account work exceeds, in the aggregate, 20 percent of the base. Excessive use of Force..., appropriate fee reductions for such excessive Force account labor shall be computed as follows: (1) Determine... following adjustments shall be made to the Schedule fee amounts for complexity levels, excessive...

  19. KSC-99pp1226

    NASA Image and Video Library

    1999-10-06

    Nancy Nichols, principal of South Lake Elementary School, Titusville, Fla., joins students in teacher Michelle Butler's sixth grade class who are unwrapping computer equipment donated by Kennedy Space Center. South Lake is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

  20. A space-efficient quantum computer simulator suitable for high-speed FPGA implementation

    NASA Astrophysics Data System (ADS)

    Frank, Michael P.; Oniciuc, Liviu; Meyer-Baese, Uwe H.; Chiorescu, Irinel

    2009-05-01

    Conventional vector-based simulators for quantum computers are quite limited in the size of the quantum circuits they can handle, due to the worst-case exponential growth of even sparse representations of the full quantum state vector as a function of the number of quantum operations applied. However, this exponential-space requirement can be avoided by using general space-time tradeoffs long known to complexity theorists, which can be appropriately optimized for this particular problem in a way that also illustrates some interesting reformulations of quantum mechanics. In this paper, we describe the design and empirical space/time complexity measurements of a working software prototype of a quantum computer simulator that avoids excessive space requirements. Due to its space-efficiency, this design is well-suited to embedding in single-chip environments, permitting especially fast execution that avoids access latencies to main memory. We plan to prototype our design on a standard FPGA development board.

  1. [WebSurvCa: web-based estimation of death and survival probabilities in a cohort].

    PubMed

    Clèries, Ramon; Ameijide, Alberto; Buxó, Maria; Vilardell, Mireia; Martínez, José Miguel; Alarcón, Francisco; Cordero, David; Díez-Villanueva, Ana; Yasui, Yutaka; Marcos-Gragera, Rafael; Vilardell, Maria Loreto; Carulla, Marià; Galceran, Jaume; Izquierdo, Ángel; Moreno, Víctor; Borràs, Josep M

    2018-01-19

    Relative survival has been used as a measure of the temporal evolution of the excess risk of death of a cohort of patients diagnosed with cancer, taking into account the mortality of a reference population. Once the excess risk of death has been estimated, three probabilities can be computed at time T: 1) the crude probability of death associated with the cause of initial diagnosis (disease under study), 2) the crude probability of death associated with other causes, and 3) the probability of absolute survival in the cohort at time T. This paper presents the WebSurvCa application (https://shiny.snpstats.net/WebSurvCa/), whereby hospital-based and population-based cancer registries and registries of other diseases can estimate such probabilities in their cohorts by selecting the mortality of the relevant region (reference population). Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. The Effects of Pathological Gaming on Aggressive Behavior

    PubMed Central

    Valkenburg, Patti M.; Peter, Jochen

    2010-01-01

    Studies have shown that pathological involvement with computer or video games is related to excessive gaming binges and aggressive behavior. Our aims for this study were to longitudinally examine if pathological gaming leads to increasingly excessive gaming habits, and how pathological gaming may cause an increase in physical aggression. For this purpose, we conducted a two-wave panel study among 851 Dutch adolescents (49% female) of which 540 played games (30% female). Our analyses indicated that higher levels of pathological gaming predicted an increase in time spent playing games 6 months later. Time spent playing violent games specifically, and not just games per se, increased physical aggression. Furthermore, higher levels of pathological gaming, regardless of violent content, predicted an increase in physical aggression among boys. That this effect only applies to boys does not diminish its importance, because adolescent boys are generally the heaviest players of violent games and most susceptible to pathological involvement. PMID:20549320

  3. The effects of pathological gaming on aggressive behavior.

    PubMed

    Lemmens, Jeroen S; Valkenburg, Patti M; Peter, Jochen

    2011-01-01

    Studies have shown that pathological involvement with computer or video games is related to excessive gaming binges and aggressive behavior. Our aims for this study were to longitudinally examine if pathological gaming leads to increasingly excessive gaming habits, and how pathological gaming may cause an increase in physical aggression. For this purpose, we conducted a two-wave panel study among 851 Dutch adolescents (49% female) of which 540 played games (30% female). Our analyses indicated that higher levels of pathological gaming predicted an increase in time spent playing games 6 months later. Time spent playing violent games specifically, and not just games per se, increased physical aggression. Furthermore, higher levels of pathological gaming, regardless of violent content, predicted an increase in physical aggression among boys. That this effect only applies to boys does not diminish its importance, because adolescent boys are generally the heaviest players of violent games and most susceptible to pathological involvement.

  4. MBSSAS: A code for the computation of margules parameters and equilibrium relations in binary solid-solution aqueous-solution systems

    USGS Publications Warehouse

    Glynn, P.D.

    1991-01-01

    The computer code MBSSAS uses two-parameter Margules-type excess-free-energy of mixing equations to calculate thermodynamic equilibrium, pure-phase saturation, and stoichiometric saturation states in binary solid-solution aqueous-solution (SSAS) systems. Lippmann phase diagrams, Roozeboom diagrams, and distribution-coefficient diagrams can be constructed from the output data files, and also can be displayed by MBSSAS (on IBM-PC compatible computers). MBSSAS also will calculate accessory information, such as the location of miscibility gaps, spinodal gaps, critical-mixing points, alyotropic extrema, Henry's law solid-phase activity coefficients, and limiting distribution coefficients. Alternatively, MBSSAS can use such information (instead of the Margules, Guggenheim, or Thompson and Waldbaum excess-free-energy parameters) to calculate the appropriate excess-free-energy of mixing equation for any given SSAS system. ?? 1991.

  5. KSC-99pp1228

    NASA Image and Video Library

    1999-10-06

    Children at Cambridge Elementary School, Cocoa, Fla., eagerly unwrap computer equipment donated by Kennedy Space Center. Cambridge is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. Behind the children is Jim Thurston, a school volunteer and retired employee of USBI, who shared in the project. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

  6. Is excessive online usage a function of medium or activity? An empirical pilot study

    PubMed Central

    Griffiths, Mark D.; Szabo, Attila

    2014-01-01

    Aims: The purpose of the study was to seek a better insight into whether the online medium or the online activity was more important in relation to excessive online use. It is not clear whether those people who spend excessive amounts of time on the Internet are engaged in general Internet or whether excessive Internet use is linked to specific activities. Methods: Perceived changes in Internet use habits as function of hypothetical accessibility of favorite sites were investigated in young adults. University students (n = 130, mean age = 20.6 years) who had (on average) spent over 20 hours a week on the Internet for at least nine years completed a survey. The most favored online activities and expected quality of life without Internet access were also investigated. Results: Findings revealed that social networking was by far the most popular online activity, and that lack of access to their preferred online activities would drop by 65% (as measured by perceived Internet usage). Approximately one in six participants (16%) claimed they would not even switch on the computer if access to their favorite online activities were unavailable. In relation to a hypothetical question about the quality of life without Internet access, the responses were normally distributed (rather than skewed). Conclusions: These results show that time spent with Internet activity is not random and/or generalized, but appears more focused. Attraction or addiction on Internet to one or more specific behavior(s) may be a better way forward in the quest for better understanding excessive human behavior in the online environment. PMID:25215216

  7. Study of thermodynamic and transport properties of binary liquid mixture of diesel with biodiesel at 298.15K

    NASA Astrophysics Data System (ADS)

    Suthar, Shyam Sunder; Purohit, Suresh

    2018-05-01

    Properties of diesel and biodiesel (produced from corn oil) are used. Densities and viscosities of binary mixture of diesel with biodiesel (produced from corn oil) have been computed by using liquid binary mixture law over the entire range of compositions at T=298.15K and atmospheric pressure. From the computed values of density and viscosities, viscosity deviation (Δη), the excess molar volume (VE) and excess Gibbs energy of activation of viscous flow (ΔG#E) have been calculated. The results of excess volume, excess Gibbs energy of activation of viscous flow and viscosity deviation have been fitted to Redlich -Kister models to estimate the binary coefficients. The results are communicated in terms of the molecular interactions and the best suited composition has been found.

  8. Pediatric Trauma Transfer Imaging Inefficiencies-Opportunities for Improvement with Cloud Technology.

    PubMed

    Puckett, Yana; To, Alvin

    2016-01-01

    This study examines the inefficiencies of radiologic imaging transfers from one hospital to the other during pediatric trauma transfers in an era of cloud based information sharing. Retrospective review of all patients transferred to a pediatric trauma center from 2008-2014 was performed. Imaging was reviewed for whether imaging accompanied the patient, whether imaging was able to be uploaded onto computer for records, whether imaging had to be repeated, and whether imaging obtained at outside hospitals (OSH) was done per universal pediatric trauma guidelines. Of the 1761 patients retrospectively reviewed, 559 met our inclusion criteria. Imaging was sent with the patient 87.7% of the time. Imaging was unable to be uploaded 31.9% of the time. CT imaging had to be repeated 1.8% of the time. CT scan was not done per universal pediatric trauma guidelines 1.2% of the time. Our study demonstrated that current imaging transfer is inefficient, leads to excess ionizing radiation, and increased healthcare costs. Universal implementation of cloud based radiology has the potential to eliminate excess ionizing radiation to children, improve patient care, and save cost to healthcare system.

  9. Steady-State Computation of Constant Rotational Rate Dynamic Stability Derivatives

    NASA Technical Reports Server (NTRS)

    Park, Michael A.; Green, Lawrence L.

    2000-01-01

    Dynamic stability derivatives are essential to predicting the open and closed loop performance, stability, and controllability of aircraft. Computational determination of constant-rate dynamic stability derivatives (derivatives of aircraft forces and moments with respect to constant rotational rates) is currently performed indirectly with finite differencing of multiple time-accurate computational fluid dynamics solutions. Typical time-accurate solutions require excessive amounts of computational time to complete. Formulating Navier-Stokes (N-S) equations in a rotating noninertial reference frame and applying an automatic differentiation tool to the modified code has the potential for directly computing these derivatives with a single, much faster steady-state calculation. The ability to rapidly determine static and dynamic stability derivatives by computational methods can benefit multidisciplinary design methodologies and reduce dependency on wind tunnel measurements. The CFL3D thin-layer N-S computational fluid dynamics code was modified for this study to allow calculations on complex three-dimensional configurations with constant rotation rate components in all three axes. These CFL3D modifications also have direct application to rotorcraft and turbomachinery analyses. The modified CFL3D steady-state calculation is a new capability that showed excellent agreement with results calculated by a similar formulation. The application of automatic differentiation to CFL3D allows the static stability and body-axis rate derivatives to be calculated quickly and exactly.

  10. Adaptive allocation of decisionmaking responsibility between human and computer in multitask situations

    NASA Technical Reports Server (NTRS)

    Chu, Y.-Y.; Rouse, W. B.

    1979-01-01

    As human and computer come to have overlapping decisionmaking abilities, a dynamic or adaptive allocation of responsibilities may be the best mode of human-computer interaction. It is suggested that the computer serve as a backup decisionmaker, accepting responsibility when human workload becomes excessive and relinquishing responsibility when workload becomes acceptable. A queueing theory formulation of multitask decisionmaking is used and a threshold policy for turning the computer on/off is proposed. This policy minimizes event-waiting cost subject to human workload constraints. An experiment was conducted with a balanced design of several subject runs within a computer-aided multitask flight management situation with different task demand levels. It was found that computer aiding enhanced subsystem performance as well as subjective ratings. The queueing model appears to be an adequate representation of the multitask decisionmaking situation, and to be capable of predicting system performance in terms of average waiting time and server occupancy. Server occupancy was further found to correlate highly with the subjective effort ratings.

  11. Computational method for the correction of proximity effect in electron-beam lithography (Poster Paper)

    NASA Astrophysics Data System (ADS)

    Chang, Chih-Yuan; Owen, Gerry; Pease, Roger Fabian W.; Kailath, Thomas

    1992-07-01

    Dose correction is commonly used to compensate for the proximity effect in electron lithography. The computation of the required dose modulation is usually carried out using 'self-consistent' algorithms that work by solving a large number of simultaneous linear equations. However, there are two major drawbacks: the resulting correction is not exact, and the computation time is excessively long. A computational scheme, as shown in Figure 1, has been devised to eliminate this problem by the deconvolution of the point spread function in the pattern domain. The method is iterative, based on a steepest descent algorithm. The scheme has been successfully tested on a simple pattern with a minimum feature size 0.5 micrometers , exposed on a MEBES tool at 10 KeV in 0.2 micrometers of PMMA resist on a silicon substrate.

  12. Definition of temperature thresholds: the example of the French heat wave warning system.

    PubMed

    Pascal, Mathilde; Wagner, Vérène; Le Tertre, Alain; Laaidi, Karine; Honoré, Cyrille; Bénichou, Françoise; Beaudeau, Pascal

    2013-01-01

    Heat-related deaths should be somewhat preventable. In France, some prevention measures are activated when minimum and maximum temperatures averaged over three days reach city-specific thresholds. The current thresholds were computed based on a descriptive analysis of past heat waves and on local expert judgement. We tested whether a different method would confirm these thresholds. The study was set in the six cities of Paris, Lyon, Marseille, Nantes, Strasbourg and Limoges between 1973 and 2003. For each city, we estimated the excess in mortality associated with different temperature thresholds, using a generalised additive model, controlling for long-time trends, seasons and days of the week. These models were used to compute the mortality predicted by different percentiles of temperatures. The thresholds were chosen as the percentiles associated with a significant excess mortality. In all cities, there was a good correlation between current thresholds and the thresholds derived from the models, with 0°C to 3°C differences for averaged maximum temperatures. Both set of thresholds were able to anticipate the main periods of excess mortality during the summers of 1973 to 2003. A simple method relying on descriptive analysis and expert judgement is sufficient to define protective temperature thresholds and to prevent heat wave mortality. As temperatures are increasing along with the climate change and adaptation is ongoing, more research is required to understand if and when thresholds should be modified.

  13. Insomnia symptoms among Greek adolescent students with excessive computer use

    PubMed Central

    Siomos, K E; Braimiotis, D; Floros, G D; Dafoulis, V; Angelopoulos, N V

    2010-01-01

    Background: The aim of the present study is to assess the intensity of computer use and insomnia epidemiology among Greek adolescents, to examine any possible age and gender differences and to investigate whether excessive computer use is a risk factor for developing insomnia symptoms. Patients and Methods: Cross-sectional study of a stratified sample of 2195 high school students. Demographic data were recorded and two specific questionnaires were used, the Adolescent Computer Addiction Test (ACAT) and the Athens Insomnia Scale (AIS). Results: Females scored higher than males on insomnia complaints but lower on computer use and addiction. A dosemediated effect of computer use on insomnia complaints was recorded. Computer use had a larger effect size than sex on insomnia complaints. Duration of computer use was longer for those adolescents classified as suffering from insomnia compared to those who were not. Conclusions: Computer use can be a significant cause of insomnia complaints in an adolescent population regardless of whether the individual is classified as addicted or not. PMID:20981171

  14. Pre-development conditions to assess the impact of growth in an urbanizing watershed in Northern Virginia

    NASA Astrophysics Data System (ADS)

    Kumar, Saurav; Godrej, Adil N.; Grizzard, Thomas J.

    2016-09-01

    Pre-development conditions are an easily understood state to which watershed nonpoint nutrient reduction targets may be referenced. Using the pre-development baseline, a "developed-excess" measure may be computed for changes due to anthropogenic development. Developed-excess is independent of many geographical, physical, and hydrological characteristics of the region and after normalization by area may be used for comparison among various sub-sets of the watershed, such as jurisdictions or land use types. We have demonstrated this method by computing pre-development nitrogen and phosphorus loads entering the Occoquan Reservoir from its tributary watershed in Northern Virginia. The pre-development loads in this study were computed using the calibrated water quality models for the period 2002-2007. Current forest land was used as a surrogate for pre-development land use conditions for the watershed and developed-excess was estimated for fluvial loads of Total Inorganic Nitrogen (TIN) and Orthophosphate-Phosphorus (OP) by subtracting simulated predevelopment loads from observed loads. It was observed that within the study period (2002-2007), the average annual developed-excess represented about 30% of the TIN and OP average annual loads exported to the reservoir. Comparison of the two disturbed land use types, urban and agricultural, showed that urban land uses exported significantly more excess nonpoint nutrient load per unit area than agricultural land uses.

  15. Macular Carotenoid Supplementation Improves Visual Performance, Sleep Quality, and Adverse Physical Symptoms in Those with High Screen Time Exposure.

    PubMed

    Stringham, James M; Stringham, Nicole T; O'Brien, Kevin J

    2017-06-29

    The dramatic rise in the use of smartphones, tablets, and laptop computers over the past decade has raised concerns about potentially deleterious health effects of increased "screen time" (ST) and associated short-wavelength (blue) light exposure. We determined baseline associations and effects of 6 months' supplementation with the macular carotenoids (MC) lutein, zeaxanthin, and mesozeaxanthin on the blue-absorbing macular pigment (MP) and measures of sleep quality, visual performance, and physical indicators of excessive ST. Forty-eight healthy young adults with at least 6 h of daily near-field ST exposure participated in this placebo-controlled trial. Visual performance measures included contrast sensitivity, critical flicker fusion, disability glare, and photostress recovery. Physical indicators of excessive screen time and sleep quality were assessed via questionnaire. MP optical density (MPOD) was assessed via heterochromatic flicker photometry. At baseline, MPOD was correlated significantly with all visual performance measures ( p < 0.05 for all). MC supplementation (24 mg daily) yielded significant improvement in MPOD, overall sleep quality, headache frequency, eye strain, eye fatigue, and all visual performance measures, versus placebo ( p < 0.05 for all). Increased MPOD significantly improves visual performance and, in turn, improves several undesirable physical outcomes associated with excessive ST. The improvement in sleep quality was not directly related to increases in MPOD, and may be due to systemic reduction in oxidative stress and inflammation.

  16. The relationship between TV/computer time and adolescents' health-promoting behavior: a secondary data analysis.

    PubMed

    Chen, Mei-Yen; Liou, Yiing-Mei; Wu, Jen-Yee

    2008-03-01

    Television and computers provide significant benefits for learning about the world. Some studies have linked excessive television (TV) watching or computer game playing to disadvantage of health status or some unhealthy behavior among adolescents. However, the relationships between watching TV/playing computer games and adolescents adopting health promoting behavior were limited. This study aimed to discover the relationship between time spent on watching TV and on leisure use of computers and adolescents' health promoting behavior, and associated factors. This paper used secondary data analysis from part of a health promotion project in Taoyuan County, Taiwan. A cross-sectional design was used and purposive sampling was conducted among adolescents in the original project. A total of 660 participants answered the questions appropriately for this work between January and June 2004. Findings showed the mean age of the respondents was 15.0 +/- 1.7 years. The mean numbers of TV watching hours were 2.28 and 4.07 on weekdays and weekends respectively. The mean hours of leisure (non-academic) computer use were 1.64 and 3.38 on weekdays and weekends respectively. Results indicated that adolescents spent significant time watching TV and using the computer, which was negatively associated with adopting health-promoting behaviors such as life appreciation, health responsibility, social support and exercise behavior. Moreover, being boys, being overweight, living in a rural area, and being middle-school students were significantly associated with spending long periods watching TV and using the computer. Therefore, primary health care providers should record the TV and non-academic computer time of youths when conducting health promotion programs, and educate parents on how to become good and healthy electronic media users.

  17. 77 FR 26660 - Guidelines for the Transfer of Excess Computers or Other Technical Equipment Pursuant to Section...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-07

    ....usda.gov . SUPPLEMENTARY INFORMATION: A. Background A proposed rule was published in the Federal.... Computers or other technical equipment means central processing units, laptops, desktops, computer mouses...

  18. Experimentally validated computational modeling of organic binder burnout from green ceramic compacts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ewsuk, K.G.; Cochran, R.J.; Blackwell, B.F.

    The properties and performance of a ceramic component is determined by a combination of the materials from which it was fabricated and how it was processed. Most ceramic components are manufactured by dry pressing a powder/binder system in which the organic binder provides formability and green compact strength. A key step in this manufacturing process is the removal of the binder from the powder compact after pressing. The organic binder is typically removed by a thermal decomposition process in which heating rate, temperature, and time are the key process parameters. Empirical approaches are generally used to design the burnout time-temperaturemore » cycle, often resulting in excessive processing times and energy usage, and higher overall manufacturing costs. Ideally, binder burnout should be completed as quickly as possible without damaging the compact, while using a minimum of energy. Process and computational modeling offer one means to achieve this end. The objective of this study is to develop an experimentally validated computer model that can be used to better understand, control, and optimize binder burnout from green ceramic compacts.« less

  19. SAGE: The Self-Adaptive Grid Code. 3

    NASA Technical Reports Server (NTRS)

    Davies, Carol B.; Venkatapathy, Ethiraj

    1999-01-01

    The multi-dimensional self-adaptive grid code, SAGE, is an important tool in the field of computational fluid dynamics (CFD). It provides an efficient method to improve the accuracy of flow solutions while simultaneously reducing computer processing time. Briefly, SAGE enhances an initial computational grid by redistributing the mesh points into more appropriate locations. The movement of these points is driven by an equal-error-distribution algorithm that utilizes the relationship between high flow gradients and excessive solution errors. The method also provides a balance between clustering points in the high gradient regions and maintaining the smoothness and continuity of the adapted grid, The latest version, Version 3, includes the ability to change the boundaries of a given grid to more efficiently enclose flow structures and provides alternative redistribution algorithms.

  20. 10 CFR Appendix I to Part 504 - Procedures for the Computation of the Real Cost of Capital

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    .... Government 13-week Treasury Bills, B=The “beta” coefficient—the relationship between the excess return on common stock and the excess return on the S&P 500 composite index, and R m=The mean excess return on the... statements of firms, and investment bankers. (2) The predicted nominal cost of debt (R d) may be estimated by...

  1. Validity and extension of the SCS-CN method for computing infiltration and rainfall-excess rates

    NASA Astrophysics Data System (ADS)

    Mishra, Surendra Kumar; Singh, Vijay P.

    2004-12-01

    A criterion is developed for determining the validity of the Soil Conservation Service curve number (SCS-CN) method. According to this criterion, the existing SCS-CN method is found to be applicable when the potential maximum retention, S, is less than or equal to twice the total rainfall amount. The criterion is tested using published data of two watersheds. Separating the steady infiltration from capillary infiltration, the method is extended for predicting infiltration and rainfall-excess rates. The extended SCS-CN method is tested using 55 sets of laboratory infiltration data on soils varying from Plainfield sand to Yolo light clay, and the computed and observed infiltration and rainfall-excess rates are found to be in good agreement.

  2. A fast, programmable hardware architecture for the processing of spaceborne SAR data

    NASA Technical Reports Server (NTRS)

    Bennett, J. R.; Cumming, I. G.; Lim, J.; Wedding, R. M.

    1984-01-01

    The development of high-throughput SAR processors (HTSPs) for the spaceborne SARs being planned by NASA, ESA, DFVLR, NASDA, and the Canadian Radarsat Project is discussed. The basic parameters and data-processing requirements of the SARs are listed in tables, and the principal problems are identified as real-operations rates in excess of 2 x 10 to the 9th/sec, I/O rates in excess of 8 x 10 to the 6th samples/sec, and control computation loads (as for range cell migration correction) as high as 1.4 x 10 to the 6th instructions/sec. A number of possible HTSP architectures are reviewed; host/array-processor (H/AP) and distributed-control/data-path (DCDP) architectures are examined in detail and illustrated with block diagrams; and a cost/speed comparison of these two architectures is presented. The H/AP approach is found to be adequate and economical for speeds below 1/200 of real time, while DCDP is more cost-effective above 1/50 of real time.

  3. Real-time calculation of a limiting form of the Renyi entropy applied to detection of subtle changes in scattering architecture

    PubMed Central

    Hughes, M. S.; McCarthy, J. E.; Wickerhauser, M. V.; Marsh, J. N.; Arbeit, J. M.; Fuhrhop, R. W.; Wallace, K. D.; Thomas, T.; Smith, J.; Agyem, K.; Lanza, G. M.; Wickline, S. A.

    2009-01-01

    Previously a new method for ultrasound signal characterization using entropy Hf was reported, and it was demonstrated that in certain settings, further improvements in signal characterization could be obtained by generalizing to Renyi entropy-based signal characterization If(r) with values of r near 2 (specifically r=1.99) [M. S. Hughes et al., J. Acoust. Soc. Am. 125, 3141–3145 (2009)]. It was speculated that further improvements in sensitivity might be realized at the limit r→2. At that time, such investigation was not feasible due to excessive computational time required to calculate If(r) near this limit. In this paper, an asymptotic expression for the limiting behavior of If(r) as r→2 is derived and used to present results analogous to those obtained with If(1.99). Moreover, the limiting form If,∞ is computable directly from the experimentally measured waveform f(t) by an algorithm that is suitable for real-time calculation and implementation. PMID:19894818

  4. A computer program to perform dynamic thermal analysis for bare overhead conductors during short-time overload conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shrestha, P.; Pham, K.

    1995-12-31

    Under emergency conditions, a bare overhead conductor can carry an increased amount of current that is well in excess of its normal rating. When there is this increase in current flow on a bare overhead conductor, the temperature does not rise instantaneously. but increases along a curve determined by the current, the conductor properties and the ambient conditions. The conductor temperature at the end of a short-time overload period must be restricted to its maximum design value. This paper presents a simplified approach in analyzing the dynamic performance for bare overhead conductors during short-time overload condition. A computer program wasmore » developed to calculate the short-time ratings for bare overhead conductors. The following parameters: current induced heating. solar load, convective/conductive cooling, radiative cooling, altitude, wind velocity and ampacity of the bare conductor were considered. Several sample graphical output lots are included with the paper.« less

  5. Configuring Airspace Sectors with Approximate Dynamic Programming

    NASA Technical Reports Server (NTRS)

    Bloem, Michael; Gupta, Pramod

    2010-01-01

    In response to changing traffic and staffing conditions, supervisors dynamically configure airspace sectors by assigning them to control positions. A finite horizon airspace sector configuration problem models this supervisor decision. The problem is to select an airspace configuration at each time step while considering a workload cost, a reconfiguration cost, and a constraint on the number of control positions at each time step. Three algorithms for this problem are proposed and evaluated: a myopic heuristic, an exact dynamic programming algorithm, and a rollouts approximate dynamic programming algorithm. On problem instances from current operations with only dozens of possible configurations, an exact dynamic programming solution gives the optimal cost value. The rollouts algorithm achieves costs within 2% of optimal for these instances, on average. For larger problem instances that are representative of future operations and have thousands of possible configurations, excessive computation time prohibits the use of exact dynamic programming. On such problem instances, the rollouts algorithm reduces the cost achieved by the heuristic by more than 15% on average with an acceptable computation time.

  6. Exercise-associated Excessive Dynamic Airway Collapse in Military Personnel.

    PubMed

    Weinstein, Daniel J; Hull, James E; Ritchie, Brittany L; Hayes, Jackie A; Morris, Michael J

    2016-09-01

    Evaluation of military personnel for exertional dyspnea can present a diagnostic challenge, given multiple unique factors that include wide variation in military deployment. Initial consideration is given to common disorders such as asthma, exercise-induced bronchospasm, and inducible laryngeal obstruction. Excessive dynamic airway collapse has not been reported previously as a cause of dyspnea in these individuals. To describe the clinical and imaging characteristics of military personnel with exertional dyspnea who were found to have excessive dynamic collapse of large airways during exercise. After deployment to Afghanistan or Iraq, 240 active U.S. military personnel underwent a standardized evaluation to determine the etiology of persistent dyspnea on exertion. Study procedures included full pulmonary function testing, impulse oscillometry, exhaled nitric oxide measurement, methacholine challenge testing, exercise laryngoscopy, cardiopulmonary exercise testing, and fiberoptic bronchoscopy. Imaging included high-resolution computed tomography with inspiratory and expiratory views. Selected individuals underwent further imaging with dynamic computed tomography. A total of five men and one woman were identified as having exercise-associated excessive dynamic airway collapse on the basis of the following criteria: (1) exertional dyspnea without resting symptoms, (2) focal expiratory wheezing during exercise, (3) functional collapse of the large airways during bronchoscopy, (4) expiratory computed tomographic imaging showing narrowing of a large airway, and (5) absence of underlying apparent pathology in small airways or pulmonary parenchyma. Identification of focal expiratory wheezing correlated with bronchoscopic and imaging findings. Among 240 military personnel evaluated after presenting with postdeployment exertional dyspnea, a combination of symptoms, auscultatory findings, imaging, and visualization of the airways by bronchoscopy identified six individuals with excessive dynamic central airway collapse as the sole apparent cause of dyspnea. Exercise-associated excessive dynamic airway collapse should be considered in the differential diagnosis of exertional dyspnea.

  7. GAPIT: genome association and prediction integrated tool.

    PubMed

    Lipka, Alexander E; Tian, Feng; Wang, Qishan; Peiffer, Jason; Li, Meng; Bradbury, Peter J; Gore, Michael A; Buckler, Edward S; Zhang, Zhiwu

    2012-09-15

    Software programs that conduct genome-wide association studies and genomic prediction and selection need to use methodologies that maximize statistical power, provide high prediction accuracy and run in a computationally efficient manner. We developed an R package called Genome Association and Prediction Integrated Tool (GAPIT) that implements advanced statistical methods including the compressed mixed linear model (CMLM) and CMLM-based genomic prediction and selection. The GAPIT package can handle large datasets in excess of 10 000 individuals and 1 million single-nucleotide polymorphisms with minimal computational time, while providing user-friendly access and concise tables and graphs to interpret results. http://www.maizegenetics.net/GAPIT. zhiwu.zhang@cornell.edu Supplementary data are available at Bioinformatics online.

  8. Computer simulation of production from geopressured-geothermal aquifers. Project 61025 annual report, October 1, 1978-September 30, 1979

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rogers, L.A.

    1980-06-01

    In the Department of Energy test of the Edna Delcambre No. 1 well for recovery of natural gas from geopressured-geothermal brine, part of the test producted gas in excess of the amount that could be dissolved in the brine. Where this excess gas originated was unknown and several theories were proposed to explain the source. This annual report describes IGT's work to match the observed gas/water production with computer simulation. Two different theoretical models were calculated in detail using available reservoir simulators. One model considered the excess gas to be dispersed as small bubbles in pores. The other model consideredmore » the excess gas as a nearby free gas cap above the aquifer. Reservoir engineering analysis of the flow test data was used to determine the basic reservoir characteristics. The computer studies revealed that the dispersed gas model gave characteristically the wrong shape for plots of gas/water ratio, and no reasonable match of the calculated values could be made to the experimental results. The free gas cap model gave characteristically better shapes to the gas/water ratio plots if the initial edge of the free gas was only about 400 feet from the well. Because there were two other wells at approximately this distance (Delcambre No. 4 and No. 4A wells) which had a history of down-hole blowouts and mechanical problems, it appears that the source of the excess free gas is from a separate horizon which connected to the Delcambre No. 1 sand via these nearby wells. This conclusion is corroborated by the changes in gas composition when the excess gas occurs and the geological studies which indicate the nearest free gas cap to be several thousand feet away. The occurrence of this excess free gas can thus be explained by known reservoir characteristics, and no new model for gas entrapment or production is needed.« less

  9. Error processing and response inhibition in excessive computer game players: an event-related potential study.

    PubMed

    Littel, Marianne; van den Berg, Ivo; Luijten, Maartje; van Rooij, Antonius J; Keemink, Lianne; Franken, Ingmar H A

    2012-09-01

    Excessive computer gaming has recently been proposed as a possible pathological illness. However, research on this topic is still in its infancy and underlying neurobiological mechanisms have not yet been identified. The determination of underlying mechanisms of excessive gaming might be useful for the identification of those at risk, a better understanding of the behavior and the development of interventions. Excessive gaming has been often compared with pathological gambling and substance use disorder. Both disorders are characterized by high levels of impulsivity, which incorporates deficits in error processing and response inhibition. The present study aimed to investigate error processing and response inhibition in excessive gamers and controls using a Go/NoGo paradigm combined with event-related potential recordings. Results indicated that excessive gamers show reduced error-related negativity amplitudes in response to incorrect trials relative to correct trials, implying poor error processing in this population. Furthermore, excessive gamers display higher levels of self-reported impulsivity as well as more impulsive responding as reflected by less behavioral inhibition on the Go/NoGo task. The present study indicates that excessive gaming partly parallels impulse control and substance use disorders regarding impulsivity measured on the self-reported, behavioral and electrophysiological level. Although the present study does not allow drawing firm conclusions on causality, it might be that trait impulsivity, poor error processing and diminished behavioral response inhibition underlie the excessive gaming patterns observed in certain individuals. They might be less sensitive to negative consequences of gaming and therefore continue their behavior despite adverse consequences. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.

  10. Television, reading, and computer time: correlates of school-day leisure-time sedentary behavior and relationship with overweight in children in the U.S.

    PubMed

    Sisson, Susan B; Broyles, Stephanie T; Baker, Birgitta L; Katzmarzyk, Peter T

    2011-09-01

    The purposes were 1) to determine if different leisure-time sedentary behaviors (LTSB), such as TV/video/video game viewing/playing (TV), reading for pleasure (reading), and nonschool computer usage, were associated with childhood overweight status, and 2) to assess the social-ecological correlates of LTSB. The analytic sample was 33,117 (16,952 boys and 16,165 girls) participants from the 2003 National Survey of Children's Health. The cut-point for excessive TV and nonschool computer usage was ≥ 2 hr/day. High quantities of daily reading for pleasure were classified as ≥ 31 min/day. Weighted descriptive characteristics were calculated on the sample (means ± SE or frequency). Logistic regression models were used to determine if the LTSB were associated with overweight status and to examine social-ecological correlates. Over 35% of the sample was overweight. Odds of being overweight were higher in the 2 to 3 hr/day (OR: 1.48, 95% CI: 1.24, 1.76) and ≥ 4 hr/day (OR: 1.52, 95% CI: 1.22, 1.91) daily TV groups compared with none. Reading and nonschool computer usage was not associated with being overweight. TV was associated with overweight classification; however, nonschool computer usage and reading were not. Several individual, family, and community correlates were associated with high volumes of daily TV viewing.

  11. Planning for distributed workflows: constraint-based coscheduling of computational jobs and data placement in distributed environments

    NASA Astrophysics Data System (ADS)

    Makatun, Dzmitry; Lauret, Jérôme; Rudová, Hana; Šumbera, Michal

    2015-05-01

    When running data intensive applications on distributed computational resources long I/O overheads may be observed as access to remotely stored data is performed. Latencies and bandwidth can become the major limiting factor for the overall computation performance and can reduce the CPU/WallTime ratio to excessive IO wait. Reusing the knowledge of our previous research, we propose a constraint programming based planner that schedules computational jobs and data placements (transfers) in a distributed environment in order to optimize resource utilization and reduce the overall processing completion time. The optimization is achieved by ensuring that none of the resources (network links, data storages and CPUs) are oversaturated at any moment of time and either (a) that the data is pre-placed at the site where the job runs or (b) that the jobs are scheduled where the data is already present. Such an approach eliminates the idle CPU cycles occurring when the job is waiting for the I/O from a remote site and would have wide application in the community. Our planner was evaluated and simulated based on data extracted from log files of batch and data management systems of the STAR experiment. The results of evaluation and estimation of performance improvements are discussed in this paper.

  12. Physico-chemical properties of binary mixtures of aliphatic and aromatic solvents at 313 K on acoustical data

    NASA Astrophysics Data System (ADS)

    Dahire, S. L.; Morey, Y. C.; Agrawal, P. S.

    2015-12-01

    Density (ρ), viscosity (η), and ultrasonic velocity ( U) of binary mixtures of aliphatic solvents like dimethylformamide (DMF) and dimethylsulfoxide (DMSO) with aromatic solvents viz. chlorobenzene (CB), bromobenzene (BB), and nitrobenzene (NB) have been determined at 313 K. These parameters were used to calculate the adiabatic compressibility (β), intermolecular free length ( L f), molar volume ( V m), and acoustic impedance ( Z). From the experimental data excess molar volume ( V m E ), excess intermolecular free length ( L f E )), excess adiabatic compressibility (βE), and excess acoustic impedance ( Z E) have been computed. The excess values were correlated using Redlich-Kister polynomial equation to obtain their coefficients and standard deviations (σ).

  13. Angular-contact ball-bearing internal load estimation algorithm using runtime adaptive relaxation

    NASA Astrophysics Data System (ADS)

    Medina, H.; Mutu, R.

    2017-07-01

    An algorithm to estimate internal loads for single-row angular contact ball bearings due to externally applied thrust loads and high-operating speeds is presented. A new runtime adaptive relaxation procedure and blending function is proposed which ensures algorithm stability whilst also reducing the number of iterations needed to reach convergence, leading to an average reduction in computation time in excess of approximately 80%. The model is validated based on a 218 angular contact bearing and shows excellent agreement compared to published results.

  14. Joint Probabilistic Reasoning About Coreference and Relations of Univeral Schema

    DTIC Science & Technology

    2017-10-01

    containing Barack and Michelle Obama state that they are married. A variety of one - shot and iterative methods have addressed the alignment problem [25...speed. Most of the computation time for these linear models is spent on the dot-product between the sparse features of an example and the weights...of the model. In some cases , it is clear that the use of all of these features is excessive and the example can be correctly classified without such

  15. Elimination of numerical diffusion in 1 - phase and 2 - phase flows

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rajamaeki, M.

    1997-07-01

    The new hydraulics solution method PLIM (Piecewise Linear Interpolation Method) is capable of avoiding the excessive errors, numerical diffusion and also numerical dispersion. The hydraulics solver CFDPLIM uses PLIM and solves the time-dependent one-dimensional flow equations in network geometry. An example is given for 1-phase flow in the case when thermal-hydraulics and reactor kinetics are strongly coupled. Another example concerns oscillations in 2-phase flow. Both the example computations are not possible with conventional methods.

  16. 47 CFR 69.157 - Line port costs in excess of basic, analog service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Line port costs in excess of basic, analog service. 69.157 Section 69.157 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED) ACCESS CHARGES Computation of Charges for Price Cap Local Exchange Carriers...

  17. The Effects of Pathological Gaming on Aggressive Behavior

    ERIC Educational Resources Information Center

    Lemmens, Jeroen S.; Valkenburg, Patti M.; Peter, Jochen

    2011-01-01

    Studies have shown that pathological involvement with computer or video games is related to excessive gaming binges and aggressive behavior. Our aims for this study were to longitudinally examine if pathological gaming leads to increasingly excessive gaming habits, and how pathological gaming may cause an increase in physical aggression. For this…

  18. Multidisciplinary Aerospace Systems Optimization: Computational AeroSciences (CAS) Project

    NASA Technical Reports Server (NTRS)

    Kodiyalam, S.; Sobieski, Jaroslaw S. (Technical Monitor)

    2001-01-01

    The report describes a method for performing optimization of a system whose analysis is so expensive that it is impractical to let the optimization code invoke it directly because excessive computational cost and elapsed time might result. In such situation it is imperative to have user control the number of times the analysis is invoked. The reported method achieves that by two techniques in the Design of Experiment category: a uniform dispersal of the trial design points over a n-dimensional hypersphere and a response surface fitting, and the technique of krigging. Analyses of all the trial designs whose number may be set by the user are performed before activation of the optimization code and the results are stored as a data base. That code is then executed and referred to the above data base. Two applications, one of the airborne laser system, and one of an aircraft optimization illustrate the method application.

  19. The effectiveness of element downsizing on a three-dimensional finite element model of bone trabeculae in implant biomechanics.

    PubMed

    Sato, Y; Wadamoto, M; Tsuga, K; Teixeira, E R

    1999-04-01

    More validity of finite element analysis in implant biomechanics requires element downsizing. However, excess downsizing needs computer memory and calculation time. To investigate the effectiveness of element downsizing on the construction of a three-dimensional finite element bone trabeculae model, with different element sizes (600, 300, 150 and 75 microm) models were constructed and stress induced by vertical 10 N loading was analysed. The difference in von Mises stress values between the models with 600 and 300 microm element sizes was larger than that between 300 and 150 microm. On the other hand, no clear difference of stress values was detected among the models with 300, 150 and 75 microm element sizes. Downsizing of elements from 600 to 300 microm is suggested to be effective in the construction of a three-dimensional finite element bone trabeculae model for possible saving of computer memory and calculation time in the laboratory.

  20. Real-time encoding and compression of neuronal spikes by metal-oxide memristors

    NASA Astrophysics Data System (ADS)

    Gupta, Isha; Serb, Alexantrou; Khiat, Ali; Zeitler, Ralf; Vassanelli, Stefano; Prodromakis, Themistoklis

    2016-09-01

    Advanced brain-chip interfaces with numerous recording sites bear great potential for investigation of neuroprosthetic applications. The bottleneck towards achieving an efficient bio-electronic link is the real-time processing of neuronal signals, which imposes excessive requirements on bandwidth, energy and computation capacity. Here we present a unique concept where the intrinsic properties of memristive devices are exploited to compress information on neural spikes in real-time. We demonstrate that the inherent voltage thresholds of metal-oxide memristors can be used for discriminating recorded spiking events from background activity and without resorting to computationally heavy off-line processing. We prove that information on spike amplitude and frequency can be transduced and stored in single devices as non-volatile resistive state transitions. Finally, we show that a memristive device array allows for efficient data compression of signals recorded by a multi-electrode array, demonstrating the technology's potential for building scalable, yet energy-efficient on-node processors for brain-chip interfaces.

  1. Real-time encoding and compression of neuronal spikes by metal-oxide memristors

    PubMed Central

    Gupta, Isha; Serb, Alexantrou; Khiat, Ali; Zeitler, Ralf; Vassanelli, Stefano; Prodromakis, Themistoklis

    2016-01-01

    Advanced brain-chip interfaces with numerous recording sites bear great potential for investigation of neuroprosthetic applications. The bottleneck towards achieving an efficient bio-electronic link is the real-time processing of neuronal signals, which imposes excessive requirements on bandwidth, energy and computation capacity. Here we present a unique concept where the intrinsic properties of memristive devices are exploited to compress information on neural spikes in real-time. We demonstrate that the inherent voltage thresholds of metal-oxide memristors can be used for discriminating recorded spiking events from background activity and without resorting to computationally heavy off-line processing. We prove that information on spike amplitude and frequency can be transduced and stored in single devices as non-volatile resistive state transitions. Finally, we show that a memristive device array allows for efficient data compression of signals recorded by a multi-electrode array, demonstrating the technology's potential for building scalable, yet energy-efficient on-node processors for brain-chip interfaces. PMID:27666698

  2. Examining Computer Gaming Addiction in Terms of Different Variables

    ERIC Educational Resources Information Center

    Kurt, Adile Askim; Dogan, Ezgi; Erdogmus, Yasemin Kahyaoglu; Emiroglu, Bulent Gursel

    2018-01-01

    The computer gaming addiction is one of the newer concepts that young generations face and can be defined as the excessive and problematic use of computer games leading to social and/or emotional problems. The purpose of this study is to analyse through variables the computer gaming addiction levels of secondary school students. The research was…

  3. Aerial Refueling Process Rescheduling Under Job Related Disruptions

    NASA Technical Reports Server (NTRS)

    Kaplan, Sezgin; Rabadi, Ghaith

    2011-01-01

    The Aerial Refueling Scheduling Problem (ARSP) can be defined as determining the refueling completion times for each fighter aircraft (job) on the multiple tankers (machines) to minimize the total weighted tardiness. ARSP assumes that the jobs have different release times and due dates. The ARSP is dynamic environment and unexpected events may occur. In this paper, rescheduling in the aerial refueling process with a time set of jobs will be studied to deal with job related disruptions such as the arrival of new jobs, the departure of an existing job, high deviations in the release times and changes in job priorities. In order to keep the stability and to avoid excessive computation, partial schedule repair algorithm is developed and its preliminary results are presented.

  4. Compensating for velocity truncation during subaperture polishing by controllable and time-variant tool influence functions.

    PubMed

    Dong, Zhichao; Cheng, Haobo; Tam, Hon-Yuen

    2015-02-10

    The velocity-varying regime used in deterministic subaperture polishing employs a time-invariant tool influence function (TIF) to figure localized surface errors by varying the transverse velocities of polishing tools. Desired transverse velocities have to be truncated if they exceed the maximal velocity of computer numerical control (CNC) machines, which induces excessive material removal and reduces figuring efficiency (FE). A time-variant (TV) TIF regime is presented, in which a TIF serves as a variable to compensate for excessive material removal when the transverse velocities are truncated. Compared with other methods, the TV-TIF regime exhibits better performance in terms of convergence rate, FE, and versatility; its operability can also be strengthened by a TIF library. Comparative experiments were conducted on a magnetorheological finishing machine to validate the effectiveness of the TV-TIF regime. Without a TV-TIF, the tool made an unwished dent (depth of 76 nm) at the center because of the velocity truncation problem. Through compensation with a TV-TIF, the dent was completely removed by the second figuring process, and a TV-TIF improved the FE from 0.029 to 0.066  mm(3)/h.

  5. Macular Carotenoid Supplementation Improves Visual Performance, Sleep Quality, and Adverse Physical Symptoms in Those with High Screen Time Exposure

    PubMed Central

    Stringham, James M.; Stringham, Nicole T.; O’Brien, Kevin J.

    2017-01-01

    The dramatic rise in the use of smartphones, tablets, and laptop computers over the past decade has raised concerns about potentially deleterious health effects of increased “screen time” (ST) and associated short-wavelength (blue) light exposure. We determined baseline associations and effects of 6 months’ supplementation with the macular carotenoids (MC) lutein, zeaxanthin, and mesozeaxanthin on the blue-absorbing macular pigment (MP) and measures of sleep quality, visual performance, and physical indicators of excessive ST. Forty-eight healthy young adults with at least 6 h of daily near-field ST exposure participated in this placebo-controlled trial. Visual performance measures included contrast sensitivity, critical flicker fusion, disability glare, and photostress recovery. Physical indicators of excessive screen time and sleep quality were assessed via questionnaire. MP optical density (MPOD) was assessed via heterochromatic flicker photometry. At baseline, MPOD was correlated significantly with all visual performance measures (p < 0.05 for all). MC supplementation (24 mg daily) yielded significant improvement in MPOD, overall sleep quality, headache frequency, eye strain, eye fatigue, and all visual performance measures, versus placebo (p < 0.05 for all). Increased MPOD significantly improves visual performance and, in turn, improves several undesirable physical outcomes associated with excessive ST. The improvement in sleep quality was not directly related to increases in MPOD, and may be due to systemic reduction in oxidative stress and inflammation. PMID:28661438

  6. Improving the Computational Effort of Set-Inversion-Based Prandial Insulin Delivery for Its Integration in Insulin Pumps

    PubMed Central

    León-Vargas, Fabian; Calm, Remei; Bondia, Jorge; Vehí, Josep

    2012-01-01

    Objective Set-inversion-based prandial insulin delivery is a new model-based bolus advisor for postprandial glucose control in type 1 diabetes mellitus (T1DM). It automatically coordinates the values of basal–bolus insulin to be infused during the postprandial period so as to achieve some predefined control objectives. However, the method requires an excessive computation time to compute the solution set of feasible insulin profiles, which impedes its integration into an insulin pump. In this work, a new algorithm is presented, which reduces computation time significantly and enables the integration of this new bolus advisor into current processing features of smart insulin pumps. Methods A new strategy was implemented that focused on finding the combined basal–bolus solution of interest rather than an extensive search of the feasible set of solutions. Analysis of interval simulations, inclusion of physiological assumptions, and search domain contractions were used. Data from six real patients with T1DM were used to compare the performance between the optimized and the conventional computations. Results In all cases, the optimized version yielded the basal–bolus combination recommended by the conventional method and in only 0.032% of the computation time. Simulations show that the mean number of iterations for the optimized computation requires approximately 3.59 s at 20 MHz processing power, in line with current features of smart pumps. Conclusions A computationally efficient method for basal–bolus coordination in postprandial glucose control has been presented and tested. The results indicate that an embedded algorithm within smart insulin pumps is now feasible. Nonetheless, we acknowledge that a clinical trial will be needed in order to justify this claim. PMID:23294789

  7. Scheduling quality of precise form sets which consist of tasks of circular type in GRID systems

    NASA Astrophysics Data System (ADS)

    Saak, A. E.; Kureichik, V. V.; Kravchenko, Y. A.

    2018-05-01

    Users’ demand in computer power and rise of technology favour the arrival of Grid systems. The quality of Grid systems’ performance depends on computer and time resources scheduling. Grid systems with a centralized structure of the scheduling system and user’s task are modeled by resource quadrant and re-source rectangle accordingly. A Non-Euclidean heuristic measure, which takes into consideration both the area and the form of an occupied resource region, is used to estimate scheduling quality of heuristic algorithms. The authors use sets, which are induced by the elements of square squaring, as an example of studying the adapt-ability of a level polynomial algorithm with an excess and the one with minimal deviation.

  8. An adiabatic linearized path integral approach for quantum time-correlation functions II: a cumulant expansion method for improving convergence.

    PubMed

    Causo, Maria Serena; Ciccotti, Giovanni; Bonella, Sara; Vuilleumier, Rodolphe

    2006-08-17

    Linearized mixed quantum-classical simulations are a promising approach for calculating time-correlation functions. At the moment, however, they suffer from some numerical problems that may compromise their efficiency and reliability in applications to realistic condensed-phase systems. In this paper, we present a method that improves upon the convergence properties of the standard algorithm for linearized calculations by implementing a cumulant expansion of the relevant averages. The effectiveness of the new approach is tested by applying it to the challenging computation of the diffusion of an excess electron in a metal-molten salt solution.

  9. Media use as a reason for meal skipping and fast eating in secondary school children.

    PubMed

    Van den Bulck, J; Eggermont, S

    2006-04-01

    This study examined self-reported meal skipping and eating faster than usual with the goal of watching television or playing computer games. Respondents reported their media use and indicated how often they skipped a meal to watch a favourite television programme or to play a computer game, and how often they ate faster than usual in order to watch television or play a computer game. Respondents were 2546 adolescents of 13 (first year of secondary school) and 16 years (fourth year of secondary school) of age. About one respondent in 10 skipped at least one meal every week for either television viewing or computer game playing. Weekly meal skipping for television viewing occurs more regularly in boys and first-year students, but particularly in teenagers who view 5 h or more daily (15% of the sample). The category of teenagers who play computer games four times a week or more (25.3% of the sample) is at increased risk of meal skipping; those who play more than four times a week are 10 times more likely weekly to skip a meal. A quarter of the adolescents eat faster at least once a week to be able to watch television or play a computer game. Regardless of gender and school year, teenagers' risk of eating faster progressively increases with their use of the media. Those who watch 4 h or more daily are about seven times more likely to skip a meal for television and those who play computer games at least four times a week are nine times more likely weekly to skip a meal. Unhealthy eating habits can be a side effect of heavy or excessive media use. Teenagers' use of television or game computers during nonworking or out-of-school hours partly displaces the amount of time that needs to be spent at meals. Practitioners and educators may try to encourage or restore a pattern of healthful meal consumption habits by reducing the amount of media use, and by supporting parental rule-making regarding children's eating habits and media use.

  10. Computer program for post-flight evaluation of the control surface response for an attitude controlled missile

    NASA Technical Reports Server (NTRS)

    Knauber, R. N.

    1982-01-01

    A FORTRAN IV coded computer program is presented for post-flight analysis of a missile's control surface response. It includes preprocessing of digitized telemetry data for time lags, biases, non-linear calibration changes and filtering. Measurements include autopilot attitude rate and displacement gyro output and four control surface deflections. Simple first order lags are assumed for the pitch, yaw and roll axes of control. Each actuator is also assumed to be represented by a first order lag. Mixing of pitch, yaw and roll commands to four control surfaces is assumed. A pseudo-inverse technique is used to obtain the pitch, yaw and roll components from the four measured deflections. This program has been used for over 10 years on the NASA/SCOUT launch vehicle for post-flight analysis and was helpful in detecting incipient actuator stall due to excessive hinge moments. The program is currently set up for a CDC CYBER 175 computer system. It requires 34K words of memory and contains 675 cards. A sample problem presented herein including the optional plotting requires eleven (11) seconds of central processor time.

  11. Influence of space size of abutment screw access channel on the amount of extruded excess cement and marginal accuracy of cement-retained single implant restorations.

    PubMed

    Al Amri, Mohammad D; Al-Johany, Sulieman S; Al-Qarni, Mohammed N; Al-Bakri, Ahmed S; Al-Maflehi, Nassr S; Abualsaud, Haythem S

    2018-02-01

    The detrimental effect of extruded excess cement on peri-implant tissue has been well documented. Although several techniques have been proposed to reduce this effect by decreasing the amount of extruded cement, how the space size of the abutment screw access channel (SAC) affects the amount of extruded cement and marginal accuracy is unclear. The purpose of this in vitro study was to evaluate the effect of the size of the unfilled space of the abutment SAC on the amount of extruded excess cement and the marginal accuracy of zirconia copings. Twelve implant replicas and corresponding standard abutments were attached and embedded in acrylic resin blocks. Computer-aided design and computer-aided manufacturing (CAD-CAM) zirconia copings with a uniform 30-μm cement space were fabricated by 1 dental technician using the standard method. The copings were temporarily cemented 3 times at different sizes of the left space of the SAC as follows: the nonspaced group (NS), in which the entire SAC was completely filled, the 1-mm-spaced group (1MMS), and the 2-mm-spaced group (2MMS). Abutments and crowns were ultrasonically cleaned, steam cleaned, and air-dried. The excess cement was collected and weighed. To measure the marginal accuracy, 20 measurements were made every 18 degrees along the coping margin at ×300 magnification and compared with the pre-cementation readings. One-way ANOVA was calculated to determine whether the amount of extruded excess cement differed among the 3 groups, and the Tukey test was applied for multiple comparisons (α=.05). The mean weights (mg) of extruded excess cement were NS (33.53 ±1.5), 1MMS (22.97 ±5.4), and 2MMS (15.17 ±5.9). Multiple comparisons showed significant differences in the amount of extruded excess cement among the 3 test groups (P<.001). The mean marginal discrepancy (μm) of the pre-cemented group (29.5 ±8.2) was significantly different (P<.01) from that of the NS (72.3 ±13.7), the 1MMS (70.1 ±19), and the 2MMS group (70.1 ±18.8). No significant differences were found in marginal accuracy among the 3 test groups (P=.942). Within the limitations of this in vitro study, leaving a 2-mm space in the SAC reduced the amount of extruded excess cement by 55% in comparison with the nonspaced abutments. However, no effect was found on the marginal accuracy of zirconia copings. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  12. Atomistic calculations of interface elastic properties in noncoherent metallic bilayers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mi Changwen; Jun, Sukky; Kouris, Demitris A.

    2008-02-15

    The paper describes theoretical and computational studies associated with the interface elastic properties of noncoherent metallic bicrystals. Analytical forms of interface energy, interface stresses, and interface elastic constants are derived in terms of interatomic potential functions. Embedded-atom method potentials are then incorporated into the model to compute these excess thermodynamics variables, using energy minimization in a parallel computing environment. The proposed model is validated by calculating surface thermodynamic variables and comparing them with preexisting data. Next, the interface elastic properties of several fcc-fcc bicrystals are computed. The excess energies and stresses of interfaces are smaller than those on free surfacesmore » of the same crystal orientations. In addition, no negative values of interface stresses are observed. Current results can be applied to various heterogeneous materials where interfaces assume a prominent role in the systems' mechanical behavior.« less

  13. Flood inundation extent mapping based on block compressed tracing

    NASA Astrophysics Data System (ADS)

    Shen, Dingtao; Rui, Yikang; Wang, Jiechen; Zhang, Yu; Cheng, Liang

    2015-07-01

    Flood inundation extent, depth, and duration are important factors affecting flood hazard evaluation. At present, flood inundation analysis is based mainly on a seeded region-growing algorithm, which is an inefficient process because it requires excessive recursive computations and it is incapable of processing massive datasets. To address this problem, we propose a block compressed tracing algorithm for mapping the flood inundation extent, which reads the DEM data in blocks before transferring them to raster compression storage. This allows a smaller computer memory to process a larger amount of data, which solves the problem of the regular seeded region-growing algorithm. In addition, the use of a raster boundary tracing technique allows the algorithm to avoid the time-consuming computations required by the seeded region-growing. Finally, we conduct a comparative evaluation in the Chin-sha River basin, results show that the proposed method solves the problem of flood inundation extent mapping based on massive DEM datasets with higher computational efficiency than the original method, which makes it suitable for practical applications.

  14. Radiological risk assessment of cosmic radiation at aviation altitudes (a trip from Houston Intercontinental Airport to Lagos International Airport).

    PubMed

    Enyinna, Paschal Ikenna

    2016-01-01

    Radiological risk parameters associated with aircrew members traveling from Houston Intercontinental Airport to Lagos International Airport have been computed using computer software called EPCARD (version 3.2). The mean annual effective dose of radiation was computed to be 2.94 mSv/year. This result is above the standard permissible limit of 1 mSv/year set for the public and pregnant aircrew members but below the limit set for occupationally exposed workers. The Risk of cancer mortality and excess career time cancer risk computed ranged from 3.5 × 10(-5) to 24.5 × 10(-5) (with average of 14.7 × 10(-5)) and 7 × 10(-4) to 49 × 10(-4) (with average of 29.4 × 10(-4)). Passengers and aircrew members should be aware of the extra cosmic radiation doses taken in during flights. All aircraft operators should monitor radiation doses incurred during aviation trips.

  15. Radiological risk assessment of cosmic radiation at aviation altitudes (a trip from Houston Intercontinental Airport to Lagos International Airport)

    PubMed Central

    Enyinna, Paschal Ikenna

    2016-01-01

    Radiological risk parameters associated with aircrew members traveling from Houston Intercontinental Airport to Lagos International Airport have been computed using computer software called EPCARD (version 3.2). The mean annual effective dose of radiation was computed to be 2.94 mSv/year. This result is above the standard permissible limit of 1 mSv/year set for the public and pregnant aircrew members but below the limit set for occupationally exposed workers. The Risk of cancer mortality and excess career time cancer risk computed ranged from 3.5 × 10−5 to 24.5 × 10−5 (with average of 14.7 × 10−5) and 7 × 10−4 to 49 × 10−4 (with average of 29.4 × 10−4). Passengers and aircrew members should be aware of the extra cosmic radiation doses taken in during flights. All aircraft operators should monitor radiation doses incurred during aviation trips. PMID:27651568

  16. Real-time calculation of a limiting form of the Renyi entropy applied to detection of subtle changes in scattering architecture.

    PubMed

    Hughes, M S; McCarthy, J E; Wickerhauser, M V; Marsh, J N; Arbeit, J M; Fuhrhop, R W; Wallace, K D; Thomas, T; Smith, J; Agyem, K; Lanza, G M; Wickline, S A

    2009-11-01

    Previously a new method for ultrasound signal characterization using entropy H(f) was reported, and it was demonstrated that in certain settings, further improvements in signal characterization could be obtained by generalizing to Renyi entropy-based signal characterization I(f)(r) with values of r near 2 (specifically r=1.99) [M. S. Hughes et al., J. Acoust. Soc. Am. 125, 3141-3145 (2009)]. It was speculated that further improvements in sensitivity might be realized at the limit r-->2. At that time, such investigation was not feasible due to excessive computational time required to calculate I(f)(r) near this limit. In this paper, an asymptotic expression for the limiting behavior of I(f)(r) as r-->2 is derived and used to present results analogous to those obtained with I(f)(1.99). Moreover, the limiting form I(f,infinity) is computable directly from the experimentally measured waveform f(t) by an algorithm that is suitable for real-time calculation and implementation.

  17. A hierarchy of computationally derived surgical and patient influences on metal on metal press-fit acetabular cup failure.

    PubMed

    Clarke, S G; Phillips, A T M; Bull, A M J; Cobb, J P

    2012-06-01

    The impact of anatomical variation and surgical error on excessive wear and loosening of the acetabular component of large diameter metal-on-metal hip arthroplasties was measured using a multi-factorial analysis through 112 different simulations. Each surgical scenario was subject to eight different daily loading activities using finite element analysis. Excessive wear appears to be predominantly dependent on cup orientation, with inclination error having a higher influence than version error, according to the study findings. Acetabular cup loosening, as inferred from initial implant stability, appears to depend predominantly on factors concerning the area of cup-bone contact, specifically the level of cup seating achieved and the individual patient's anatomy. The extent of press fit obtained at time of surgery did not appear to influence either mechanism of failure in this study. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Modeling of the Very Low Frequency (VLF) radio wave signal profile due to solar flares using the GEANT4 Monte Carlo simulation coupled with ionospheric chemistry

    NASA Astrophysics Data System (ADS)

    Palit, S.; Basak, T.; Mondal, S. K.; Pal, S.; Chakrabarti, S. K.

    2013-03-01

    X-ray photons emitted during solar flares cause ionization in the lower ionosphere (~ 60 to 100 km) in excess of what is expected from a quiet sun. Very Low Frequency (VLF) radio wave signals reflected from the D region are affected by this excess ionization. In this paper, we reproduce the deviation in VLF signal strength during solar flares by numerical modeling. We use GEANT4 Monte Carlo simulation code to compute the rate of ionization due to a M-class and a X-class flare. The output of the simulation is then used in a simplified ionospheric chemistry model to calculate the time variation of electron density at different altitudes in the lower ionosphere. The resulting electron density variation profile is then self-consistently used in the LWPC code to obtain the time variation of the VLF signal change. We did the modeling of the VLF signal along the NWC (Australia) to IERC/ICSP (India) propagation path and compared the results with observations. The agreement is found to be very satisfactory.

  19. [The application of ecological momentary assessment to the study of compulsive buying].

    PubMed

    Silbermann, Andrea; Henkel, Andreas; Müller, Astrid; de Zwaan, Martina

    2008-12-01

    Although compulsive buying is a disorder that has begun to receive attention from researchers in recent years, relatively little is known about the relationship between compulsive buying, mood, and daily stressful events. In our pilot study ecological momentary assessment (EMA) was used to examine the described relationships for the first time. 26 patients, who met criteria for compulsive buying, self-monitored their pathological behaviour, their momentary mood and the occurrence of stressful events four times a day on a handheld computer for a period of two weeks. On days with excessive buying behaviour patients reported significantly more daily stressful events compared to days without pathological buying. Before the buying episode patients recorded significantly more positive emotions. The most common consequence of compulsive buying was a significant decrease of positive affects. Thus the results of the current study suggest that mood states and daily stressful events are associated with compulsive buying behaviour. Although mood got worse immediately after excessive buying, this negative consequence did not reduce the frequency of pathological behaviour. This could implicate a high presence-orientation and impulsivity of the patients.

  20. Interactive vs passive screen time and nighttime sleep duration among school-aged children.

    PubMed

    Yland, Jennifer; Guan, Stanford; Emanuele, Erin; Hale, Lauren

    2015-09-01

    Insufficient sleep among school-aged children is a growing concern, as numerous studies have shown that chronic short sleep duration increases the risk of poor academic performance and specific adverse health outcomes. We examined the association between weekday nighttime sleep duration and 3 types of screen exposure: television, computer use, and video gaming. We used age 9 data from an ethnically diverse national birth cohort study, the Fragile Families and Child Wellbeing Study, to assess the association between screen time and sleep duration among 9-year-olds, using screen time data reported by both the child (n = 3269) and by the child's primary caregiver (n= 2770). Within the child-reported models, children who watched more than 2 hours of television per day had shorter sleep duration by approximately 11 minutes per night compared to those who watched less than 2 hours of television (β = -0.18; P < .001). Using the caregiver-reported models, both television and computer use were associated with reduced sleep duration. For both child- and parent-reported screen time measures, we did not find statistically significant differences in effect size across various types of screen time. Screen time from televisions and computers is associated with reduced sleep duration among 9-year-olds, using 2 sources of estimates of screen time exposure (child and parent reports). No specific type or use of screen time resulted in significantly shorter sleep duration than another, suggesting that caution should be advised against excessive use of all screens.

  1. A novel surveillance approach for disaster mental health

    PubMed Central

    Shankardass, Ketan; Subramanian, S. V.; Galea, Sandro

    2017-01-01

    Background Disasters have substantial consequences for population mental health. Social media data present an opportunity for mental health surveillance after disasters to help identify areas of mental health needs. We aimed to 1) identify specific basic emotions from Twitter for the greater New York City area during Hurricane Sandy, which made landfall on October 29, 2012, and to 2) detect and map spatial temporal clusters representing excess risk of these emotions. Methods We applied an advanced sentiment analysis on 344,957 Twitter tweets in the study area over eleven days, from October 22 to November 1, 2012, to extract basic emotions, a space-time scan statistic (SaTScan) and a geographic information system (QGIS) to detect and map excess risk of these emotions. Results Sadness and disgust were among the most prominent emotions identified. Furthermore, we noted 24 spatial clusters of excess risk of basic emotions over time: Four for anger, one for confusion, three for disgust, five for fear, five for sadness, and six for surprise. Of these, anger, confusion, disgust and fear clusters appeared pre disaster, a cluster of surprise was found peri disaster, and a cluster of sadness emerged post disaster. Conclusions We proposed a novel syndromic surveillance approach for mental health based on social media data that may support conventional approaches by providing useful additional information in the context of disaster. We showed that excess risk of multiple basic emotions could be mapped in space and time as a step towards anticipating acute stress in the population and identifying community mental health need rapidly and efficiently in the aftermath of disaster. More studies are needed to better control for bias, identify associations with reliable and valid instruments measuring mental health, and to explore computational methods for continued model-fitting, causal relationships, and ongoing evaluation. Our study may be a starting point also for more fully elaborated models that can either prospectively detect mental health risk using real-time social media data or detect excess risk of emotional reactions in areas that lack efficient infrastructure during and after disasters. As such, social media data may be used for mental health surveillance after large scale disasters to help identify areas of mental health needs and to guide us in our knowledge where we may most effectively intervene to reduce the mental health consequences of disasters. PMID:28723959

  2. A novel surveillance approach for disaster mental health.

    PubMed

    Gruebner, Oliver; Lowe, Sarah R; Sykora, Martin; Shankardass, Ketan; Subramanian, S V; Galea, Sandro

    2017-01-01

    Disasters have substantial consequences for population mental health. Social media data present an opportunity for mental health surveillance after disasters to help identify areas of mental health needs. We aimed to 1) identify specific basic emotions from Twitter for the greater New York City area during Hurricane Sandy, which made landfall on October 29, 2012, and to 2) detect and map spatial temporal clusters representing excess risk of these emotions. We applied an advanced sentiment analysis on 344,957 Twitter tweets in the study area over eleven days, from October 22 to November 1, 2012, to extract basic emotions, a space-time scan statistic (SaTScan) and a geographic information system (QGIS) to detect and map excess risk of these emotions. Sadness and disgust were among the most prominent emotions identified. Furthermore, we noted 24 spatial clusters of excess risk of basic emotions over time: Four for anger, one for confusion, three for disgust, five for fear, five for sadness, and six for surprise. Of these, anger, confusion, disgust and fear clusters appeared pre disaster, a cluster of surprise was found peri disaster, and a cluster of sadness emerged post disaster. We proposed a novel syndromic surveillance approach for mental health based on social media data that may support conventional approaches by providing useful additional information in the context of disaster. We showed that excess risk of multiple basic emotions could be mapped in space and time as a step towards anticipating acute stress in the population and identifying community mental health need rapidly and efficiently in the aftermath of disaster. More studies are needed to better control for bias, identify associations with reliable and valid instruments measuring mental health, and to explore computational methods for continued model-fitting, causal relationships, and ongoing evaluation. Our study may be a starting point also for more fully elaborated models that can either prospectively detect mental health risk using real-time social media data or detect excess risk of emotional reactions in areas that lack efficient infrastructure during and after disasters. As such, social media data may be used for mental health surveillance after large scale disasters to help identify areas of mental health needs and to guide us in our knowledge where we may most effectively intervene to reduce the mental health consequences of disasters.

  3. RES: Regularized Stochastic BFGS Algorithm

    NASA Astrophysics Data System (ADS)

    Mokhtari, Aryan; Ribeiro, Alejandro

    2014-12-01

    RES, a regularized stochastic version of the Broyden-Fletcher-Goldfarb-Shanno (BFGS) quasi-Newton method is proposed to solve convex optimization problems with stochastic objectives. The use of stochastic gradient descent algorithms is widespread, but the number of iterations required to approximate optimal arguments can be prohibitive in high dimensional problems. Application of second order methods, on the other hand, is impracticable because computation of objective function Hessian inverses incurs excessive computational cost. BFGS modifies gradient descent by introducing a Hessian approximation matrix computed from finite gradient differences. RES utilizes stochastic gradients in lieu of deterministic gradients for both, the determination of descent directions and the approximation of the objective function's curvature. Since stochastic gradients can be computed at manageable computational cost RES is realizable and retains the convergence rate advantages of its deterministic counterparts. Convergence results show that lower and upper bounds on the Hessian egeinvalues of the sample functions are sufficient to guarantee convergence to optimal arguments. Numerical experiments showcase reductions in convergence time relative to stochastic gradient descent algorithms and non-regularized stochastic versions of BFGS. An application of RES to the implementation of support vector machines is developed.

  4. Differences by Sex in Association of Mental Health With Video Gaming or Other Nonacademic Computer Use Among US Adolescents

    PubMed Central

    Sung, Jung Hye; Lee, Ji-Young; Lee, Jae Eun

    2017-01-01

    Introduction Although numerous studies have examined the association between playing video games and cognitive skills, aggression, and depression, few studies have examined how these associations differ by sex. The objective of our study was to determine differences by sex in association between video gaming or other nonacademic computer use and depressive symptoms, suicidal behavior, and being bullied among adolescents in the United States. Methods We used data from the 2015 Youth Risk Behavior Survey on 15,624 US high school students. Rao–Scott χ2 tests, which were adjusted for the complex sampling design, were conducted to assess differences by sex in the association of mental health with video gaming or other nonacademic computer use. Results Approximately one-fifth (19.4%) of adolescents spent 5 or more hours daily on video gaming or other nonacademic computer use, and 17.9% did not spend any time in those activities. A greater percentage of female adolescents than male adolescents reported spending no time (22.1% and 14.0%, respectively) or 5 hours or more (21.3% and 17.5%, respectively) in gaming and other nonacademic computer use (P < .001). The association between mental problems and video gaming or other nonacademic computer use differed by sex. Among female adolescents, prevalence of mental problems increased steadily in association with increased time spent, whereas the pattern for male adolescents followed a J-shaped curve, decreasing initially, increasing slowly, and then increasing rapidly beginning at 4 hours or more. Conclusion Female adolescents were more likely to have all 3 mental health problems than male adolescents were. Spending no time or 5 hours or more daily on video gaming or other nonacademic computer use was associated with increased mental problems among both sexes. As suggested by the J-shaped relationship, 1 hour or less spent on video gaming or other nonacademic computer use may reduce depressive symptoms, suicidal behavior, and being bullied compared with no use or excessive use. PMID:29166250

  5. Differences by Sex in Association of Mental Health With Video Gaming or Other Nonacademic Computer Use Among US Adolescents.

    PubMed

    Lee, Hogan H; Sung, Jung Hye; Lee, Ji-Young; Lee, Jae Eun

    2017-11-22

    Although numerous studies have examined the association between playing video games and cognitive skills, aggression, and depression, few studies have examined how these associations differ by sex. The objective of our study was to determine differences by sex in association between video gaming or other nonacademic computer use and depressive symptoms, suicidal behavior, and being bullied among adolescents in the United States. We used data from the 2015 Youth Risk Behavior Survey on 15,624 US high school students. Rao-Scott χ 2 tests, which were adjusted for the complex sampling design, were conducted to assess differences by sex in the association of mental health with video gaming or other nonacademic computer use. Approximately one-fifth (19.4%) of adolescents spent 5 or more hours daily on video gaming or other nonacademic computer use, and 17.9% did not spend any time in those activities. A greater percentage of female adolescents than male adolescents reported spending no time (22.1% and 14.0%, respectively) or 5 hours or more (21.3% and 17.5%, respectively) in gaming and other nonacademic computer use (P < .001). The association between mental problems and video gaming or other nonacademic computer use differed by sex. Among female adolescents, prevalence of mental problems increased steadily in association with increased time spent, whereas the pattern for male adolescents followed a J-shaped curve, decreasing initially, increasing slowly, and then increasing rapidly beginning at 4 hours or more. Female adolescents were more likely to have all 3 mental health problems than male adolescents were. Spending no time or 5 hours or more daily on video gaming or other nonacademic computer use was associated with increased mental problems among both sexes. As suggested by the J-shaped relationship, 1 hour or less spent on video gaming or other nonacademic computer use may reduce depressive symptoms, suicidal behavior, and being bullied compared with no use or excessive use.

  6. Excessive Use of Massively Multi-Player Online Role-Playing Games: A Pilot Study

    ERIC Educational Resources Information Center

    Hussain, Zaheer; Griffiths, Mark D.

    2009-01-01

    Massively multiplayer online role-playing games (MMORPGs) are one of the most interesting innovations in the area of online computer gaming. This pilot study set out to examine the psychological and social effects of online gaming using an online questionnaire with particular reference to excessive and "dependent" online gaming. A self-selecting…

  7. Evaluating Computer Screen Time and Its Possible Link to Psychopathology in the Context of Age: A Cross-Sectional Study of Parents and Children

    PubMed Central

    Ross, Sharon; Silman, Zmira; Maoz, Hagai; Bloch, Yuval

    2015-01-01

    Background Several studies have suggested that high levels of computer use are linked to psychopathology. However, there is ambiguity about what should be considered normal or over-use of computers. Furthermore, the nature of the link between computer usage and psychopathology is controversial. The current study utilized the context of age to address these questions. Our hypothesis was that the context of age will be paramount for differentiating normal from excessive use, and that this context will allow a better understanding of the link to psychopathology. Methods In a cross-sectional study, 185 parents and children aged 3–18 years were recruited in clinical and community settings. They were asked to fill out questionnaires regarding demographics, functional and academic variables, computer use as well as psychiatric screening questionnaires. Using a regression model, we identified 3 groups of normal-use, over-use and under-use and examined known factors as putative differentiators between the over-users and the other groups. Results After modeling computer screen time according to age, factors linked to over-use were: decreased socialization (OR 3.24, Confidence interval [CI] 1.23–8.55, p = 0.018), difficulty to disengage from the computer (OR 1.56, CI 1.07–2.28, p = 0.022) and age, though borderline-significant (OR 1.1 each year, CI 0.99–1.22, p = 0.058). While psychopathology was not linked to over-use, post-hoc analysis revealed that the link between increased computer screen time and psychopathology was age-dependent and solidified as age progressed (p = 0.007). Unlike computer usage, the use of small-screens and smartphones was not associated with psychopathology. Conclusions The results suggest that computer screen time follows an age-based course. We conclude that differentiating normal from over-use as well as defining over-use as a possible marker for psychiatric difficulties must be performed within the context of age. If verified by additional studies, future research should integrate those views in order to better understand the intricacies of computer over-use. PMID:26536037

  8. Evaluating Computer Screen Time and Its Possible Link to Psychopathology in the Context of Age: A Cross-Sectional Study of Parents and Children.

    PubMed

    Segev, Aviv; Mimouni-Bloch, Aviva; Ross, Sharon; Silman, Zmira; Maoz, Hagai; Bloch, Yuval

    2015-01-01

    Several studies have suggested that high levels of computer use are linked to psychopathology. However, there is ambiguity about what should be considered normal or over-use of computers. Furthermore, the nature of the link between computer usage and psychopathology is controversial. The current study utilized the context of age to address these questions. Our hypothesis was that the context of age will be paramount for differentiating normal from excessive use, and that this context will allow a better understanding of the link to psychopathology. In a cross-sectional study, 185 parents and children aged 3-18 years were recruited in clinical and community settings. They were asked to fill out questionnaires regarding demographics, functional and academic variables, computer use as well as psychiatric screening questionnaires. Using a regression model, we identified 3 groups of normal-use, over-use and under-use and examined known factors as putative differentiators between the over-users and the other groups. After modeling computer screen time according to age, factors linked to over-use were: decreased socialization (OR 3.24, Confidence interval [CI] 1.23-8.55, p = 0.018), difficulty to disengage from the computer (OR 1.56, CI 1.07-2.28, p = 0.022) and age, though borderline-significant (OR 1.1 each year, CI 0.99-1.22, p = 0.058). While psychopathology was not linked to over-use, post-hoc analysis revealed that the link between increased computer screen time and psychopathology was age-dependent and solidified as age progressed (p = 0.007). Unlike computer usage, the use of small-screens and smartphones was not associated with psychopathology. The results suggest that computer screen time follows an age-based course. We conclude that differentiating normal from over-use as well as defining over-use as a possible marker for psychiatric difficulties must be performed within the context of age. If verified by additional studies, future research should integrate those views in order to better understand the intricacies of computer over-use.

  9. [Environment and health in Taranto, southern Italy: epidemiological studies and public health recommendations].

    PubMed

    Comba, Pietro; Pirastu, Roberta; Conti, Susanna; De Santis, Marco; Iavarone, Ivano; Marsili, Giovanni; Mincuzzi, Antonia; Minelli, Giada; Manno, Valerio; Minerba, Sante; Musmeci, Loredana; Rashid, Ivan; Soggiu, Eleonora; Zona, Amerigo

    2012-01-01

    in Taranto IPS (Italian polluted site, made up of 2 municipalities) the Decree defining site boundaries lists the presence of a refinery, a steel plant, a harbour area and waste landfills together with illegal dumping sites. Previous environmental and epidemiological investigations in the area documented the presence of environmental contamination and increased mortality from respiratory and cardiovascular diseases as well as a number of cancer sites; for these same health outcomes the cohort study of residents showed increased risk both in terms of mortality and morbidity. to describe the health status of residents in Taranto IPS analyzing different health indicators available at municipal level, i.e. mortality (2003-2009), mortality time trend (1980-2008) and cancer incidence (2006-2007). the analyses were carried out for residents in Taranto IPS. Mortality update (SENTIERI Project, 2003-2009) regards 63 single or grouped causes (all ages, both genders); for a selection of causes 0-1 and 0-14 age classes were analyzed (both genders combined). Standardized mortality ratio crude (SMR) and deprivation adjusted together with 90% confidence intervals (90%CI) were computed using regional rates for comparison. Mortality time trend (1980-2008, triennial intervals) were analyzed calculating standardized rates (0-99 years, both genders, per 100,000, Italian population at 2001 Census as reference) and 90%CI. Time trends were computed for all causes, all neoplasms (and lung cancer), cardiovascular diseases (and ischemic heart diseases), respiratory diseases (also acute and chronic) and all causes infant mortality (both genders combined). For cancer incidence (2006-2007) Standardized incidence ratio (SIR) and 90%CI were calculated for both genders; incidence rates of cancer registries of the macroarea South and Islands (2005-2007) and rates of Taranto Province excluding SIN municipalities (2006-2007) were used for comparison. in Taranto IPS mortality among men is in excess in both periods (SENTIERI Project 1995-2002 and 2003-2009) for all causes, all neoplasms (including lung and pleural cancer), dementia, cardiovascular diseases (including hypertension and ischemic heart diseases), respiratory diseases (including the acute ones) and digestive diseases (including liver cirrhosis). All causes infant mortality is in excess in both periods. Time trends show that Taranto IPS rates are higher than regional average in the majority of time intervals for most causes in both genders. Rates are often higher than national average form any triennial intervals. Among males, over the whole period, mortality in Taranto IPS is higher than regional and national average for causes as lung cancer, diseases of the respiratory system, including the chronic ones. Among females, since the early Nineties, lung cancer and ischemic heart diseases are in excess in Taranto IPS. Also infant mortality is higher for the whole period in Taranto IPS than regional and national averages. Cancer incidence results show excesses for cancer sites already indicated by mortality data. mortality analyzed in the context of SENTIERI Project (1995-2002 and 2003-2009), time trend mortality (1980-2008) and cancer incidence (2006- 2007) show, in both genders, excesses for causes for which an etiologic role of environmental exposure present in Taranto IPS are either ascertained or suspected on the basis of a priori evaluation of the epidemiological evidence. The finding of excess infant mortality is of the utmost importance in public health terms. Most diseases showing an increased risk have multifactorial etiology, therefore interventions of proven efficacy, such as smoking cessation, food education, measures for cardiovascular risk reduction and breast cancer and colon screening programmes should be planned. To build a climate of confidence and trust between citizens and public institutions study results and public health actions are to be communicated objectively and transparently.

  10. Performance analysis and technical assessment of coherent lidar systems for airborne wind shear detection

    NASA Technical Reports Server (NTRS)

    Huffaker, R. Milton; Targ, Russell

    1988-01-01

    Detailed computer simulations of the lidar wind-measuring process have been conducted to evaluate the use of pulsed coherent lidar for airborne windshear monitoring. NASA data fields for an actual microburst event were used in the simulation. Both CO2 and Ho:YAG laser lidar systems performed well in the microburst test case, and were able to measure wind shear in the severe weather of this wet microburst to ranges in excess of 1.4 km. The consequent warning time gained was about 15 sec.

  11. About neighborhood counting measure metric and minimum risk metric.

    PubMed

    Argentini, Andrea; Blanzieri, Enrico

    2010-04-01

    In a 2006 TPAMI paper, Wang proposed the Neighborhood Counting Measure, a similarity measure for the k-NN algorithm. In his paper, Wang mentioned the Minimum Risk Metric (MRM), an early distance measure based on the minimization of the risk of misclassification. Wang did not compare NCM to MRM because of its allegedly excessive computational load. In this comment paper, we complete the comparison that was missing in Wang's paper and, from our empirical evaluation, we show that MRM outperforms NCM and that its running time is not prohibitive as Wang suggested.

  12. Recommendations on Model Fidelity for Wind Turbine Gearbox Simulations; NREL (National Renewable Energy Laboratory)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Keller, J.; Lacava, W.; Austin, J.

    2015-02-01

    This work investigates the minimum level of fidelity required to accurately simulate wind turbine gearboxes using state-of-the-art design tools. Excessive model fidelity including drivetrain complexity, gearbox complexity, excitation sources, and imperfections, significantly increases computational time, but may not provide a commensurate increase in the value of the results. Essential designparameters are evaluated, including the planetary load-sharing factor, gear tooth load distribution, and sun orbit motion. Based on the sensitivity study results, recommendations for the minimum model fidelities are provided.

  13. Sorption Phase of Supercritical CO2 in Silica Aerogel: Experiments and Mesoscale Computer Simulations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rother, Gernot; Vlcek, Lukas; Gruszkiewicz, Miroslaw

    2014-01-01

    Adsorption of supercritical CO2 in nanoporous silica aerogel was investigated by a combination of experiments and molecular-level computer modeling. High-pressure gravimetric and vibrating tube densimetry techniques were used to measure the mean pore fluid density and excess sorption at 35 C and 50 C and pressures of 0-200 bar. Densification of the pore fluid was observed at bulk fluid densities below 0.7 g/cm3. Far above the bulk fluid density, near-zero sorption or weak depletion effects were measured, while broad excess sorption maxima form in the vicinity of the bulk critical density region. The CO2 sorption properties are very similar formore » two aerogels with different bulk densities of 0.1 g/cm3 and 0.2 g/cm3, respectively. The spatial distribution of the confined supercritical fluid was analyzed in terms of sorption- and bulk-phase densities by means of the Adsorbed Phase Model (APM), which used data from gravimetric sorption and small-angle neutron scattering experiments. To gain more detailed insight into supercritical fluid sorption, large-scale lattice gas GCMC simulations were utilized and tuned to resemble the experimental excess sorption data. The computed three-dimensional pore fluid density distributions show that the observed maximum of the excess sorption near the critical density originates from large density fluctuations pinned to the pore walls. At this maximum, the size of these fluctuations is comparable to the prevailing pore sizes.« less

  14. Ab initio calculation of excess properties of La{sub 1−x}(Ln,An){sub x}PO{sub 4} solid solutions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Yan; JARA High-Performance Computing, Schinkelstrasse 2, 52062 Aachen; Kowalski, Piotr M., E-mail: p.kowalski@fz-juelich.de

    2014-12-15

    We used ab initio computational approach to predict the excess enthalpy of mixing and the corresponding regular/subregular model parameters for La{sub 1−x}Ln{sub x}PO{sub 4} (Ln=Ce,…, Tb) and La{sub 1−x}An{sub x}PO{sub 4} (An=Pu, Am and Cm) monazite-type solid solutions. We found that the regular model interaction parameter W computed for La{sub 1−x}Ln{sub x}PO{sub 4} solid solutions matches the few existing experimental data. Within the lanthanide series W increases quadratically with the volume mismatch between LaPO{sub 4} and LnPO{sub 4} endmembers (ΔV=V{sub LaPO{sub 4}}−V{sub LnPO{sub 4}}), so that W(kJ/mol)=0.618(ΔV(cm{sup 3}/mol)){sup 2}. We demonstrate that this relationship also fits the interaction parameters computedmore » for La{sub 1−x}An{sub x}PO{sub 4} solid solutions. This shows that lanthanides can be used as surrogates for investigation of the thermodynamic mixing properties of actinide-bearing solid solutions. - Highlights: • The excess enthalpies of mixing for monazite-type solid solutions are computed. • The excess enthalpies increase with the endmembers volume mismatch. • The relationship derived for lanthanides is transferable to La{sub 1−x}An{sub x}PO{sub 4} systems.« less

  15. Inherent Conservatism in Deterministic Quasi-Static Structural Analysis

    NASA Technical Reports Server (NTRS)

    Verderaime, V.

    1997-01-01

    The cause of the long-suspected excessive conservatism in the prevailing structural deterministic safety factor has been identified as an inherent violation of the error propagation laws when reducing statistical data to deterministic values and then combining them algebraically through successive structural computational processes. These errors are restricted to the applied stress computations, and because mean and variations of the tolerance limit format are added, the errors are positive, serially cumulative, and excessively conservative. Reliability methods circumvent these errors and provide more efficient and uniform safe structures. The document is a tutorial on the deficiencies and nature of the current safety factor and of its improvement and transition to absolute reliability.

  16. 7 CFR 3203.3 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... described in paragraph (1) of this definition. Computers or other technical equipment means central... 7 Agriculture 15 2013-01-01 2013-01-01 false Definitions. 3203.3 Section 3203.3 Agriculture..., DEPARTMENT OF AGRICULTURE GUIDELINES FOR THE TRANSFER OF EXCESS COMPUTERS OR OTHER TECHNICAL EQUIPMENT...

  17. Effects of pressure drop and superficial velocity on the bubbling fluidized bed incinerator.

    PubMed

    Wang, Feng-Jehng; Chen, Suming; Lei, Perng-Kwei; Wu, Chung-Hsing

    2007-12-01

    Since performance and operational conditions, such as superficial velocity, pressure drop, particles viodage, and terminal velocity, are difficult to measure on an incinerator, this study used computational fluid dynamics (CFD) to determine numerical solutions. The effects of pressure drop and superficial velocity on a bubbling fluidized bed incinerator (BFBI) were evaluated. Analytical results indicated that simulation models were able to effectively predict the relationship between superficial velocity and pressure drop over bed height in the BFBI. Second, the models in BFBI were simplified to simulate scale-up beds without excessive computation time. Moreover, simulation and experimental results showed that minimum fluidization velocity of the BFBI must be controlled in at 0.188-3.684 m/s and pressure drop was mainly caused by bed particles.

  18. 10 CFR Appendix B to Subpart D of... - Contract Provisions

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... in excess of $100,000 for construction and other purposes that involve the employment of mechanics or... 5). Under Section 102 of the Act, each contractor is required to compute the wages of every mechanic... basic rate of pay for all hours worked in excess of 40 hours in the work week. Section 107 of the Act is...

  19. 10 CFR Appendix B to Subpart D of... - Contract Provisions

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... in excess of $100,000 for construction and other purposes that involve the employment of mechanics or... 5). Under Section 102 of the Act, each contractor is required to compute the wages of every mechanic... basic rate of pay for all hours worked in excess of 40 hours in the work week. Section 107 of the Act is...

  20. 10 CFR Appendix B to Subpart D of... - Contract Provisions

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... in excess of $100,000 for construction and other purposes that involve the employment of mechanics or... 5). Under Section 102 of the Act, each contractor is required to compute the wages of every mechanic... basic rate of pay for all hours worked in excess of 40 hours in the work week. Section 107 of the Act is...

  1. 10 CFR Appendix B to Subpart D of... - Contract Provisions

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... in excess of $100,000 for construction and other purposes that involve the employment of mechanics or... 5). Under Section 102 of the Act, each contractor is required to compute the wages of every mechanic... basic rate of pay for all hours worked in excess of 40 hours in the work week. Section 107 of the Act is...

  2. 26 CFR 1.860E-1 - Treatment of taxable income of a residual interest holder in excess of daily accruals.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... equals the product of the present value of the anticipated excess inclusions and the highest rate of tax... sufficient to satisfy the accrued taxes. (3) Computations. The present value of the expected future... formula test if the present value of the anticipated tax liabilities associated with holding the residual...

  3. 26 CFR 1.860E-1 - Treatment of taxable income of a residual interest holder in excess of daily accruals.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... equals the product of the present value of the anticipated excess inclusions and the highest rate of tax... sufficient to satisfy the accrued taxes. (3) Computations. The present value of the expected future... formula test if the present value of the anticipated tax liabilities associated with holding the residual...

  4. 26 CFR 1.860E-1 - Treatment of taxable income of a residual interest holder in excess of daily accruals.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... equals the product of the present value of the anticipated excess inclusions and the highest rate of tax... sufficient to satisfy the accrued taxes. (3) Computations. The present value of the expected future... formula test if the present value of the anticipated tax liabilities associated with holding the residual...

  5. 26 CFR 1.860E-1 - Treatment of taxable income of a residual interest holder in excess of daily accruals.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... equals the product of the present value of the anticipated excess inclusions and the highest rate of tax... sufficient to satisfy the accrued taxes. (3) Computations. The present value of the expected future... formula test if the present value of the anticipated tax liabilities associated with holding the residual...

  6. 26 CFR 1.860E-1 - Treatment of taxable income of a residual interest holder in excess of daily accruals.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... equals the product of the present value of the anticipated excess inclusions and the highest rate of tax... sufficient to satisfy the accrued taxes. (3) Computations. The present value of the expected future... formula test if the present value of the anticipated tax liabilities associated with holding the residual...

  7. Phosphorus Transport in Rivers.

    DTIC Science & Technology

    1978-11-01

    be attributed to excessive nutrient inputs to the lake. These nutrients sti- mulate the phytoplankton (algae) growth which yields excess growth. The...phosphorus in relation to the restoration of Lake Erie. The various computational techniques presented herein aid in the understanding of total...as caused by the absorption on clay materials and by assimilation by periphyton . Other investigators have found correlations between flow and other

  8. Chemotherapy appointment scheduling under uncertainty using mean-risk stochastic integer programming.

    PubMed

    Alvarado, Michelle; Ntaimo, Lewis

    2018-03-01

    Oncology clinics are often burdened with scheduling large volumes of cancer patients for chemotherapy treatments under limited resources such as the number of nurses and chairs. These cancer patients require a series of appointments over several weeks or months and the timing of these appointments is critical to the treatment's effectiveness. Additionally, the appointment duration, the acuity levels of each appointment, and the availability of clinic nurses are uncertain. The timing constraints, stochastic parameters, rising treatment costs, and increased demand of outpatient oncology clinic services motivate the need for efficient appointment schedules and clinic operations. In this paper, we develop three mean-risk stochastic integer programming (SIP) models, referred to as SIP-CHEMO, for the problem of scheduling individual chemotherapy patient appointments and resources. These mean-risk models are presented and an algorithm is devised to improve computational speed. Computational results were conducted using a simulation model and results indicate that the risk-averse SIP-CHEMO model with the expected excess mean-risk measure can decrease patient waiting times and nurse overtime when compared to deterministic scheduling algorithms by 42 % and 27 %, respectively.

  9. Global burden of cancer attributable to high body-mass index in 2012: a population-based study

    PubMed Central

    Byrnes, Graham; Renehan, Prof Andrew G; Stevens, Gretchen A; Ezzati, Prof Majid; Ferlay, Jacques; Miranda, J. Jaime; Romieu, Isabelle; Dikshit, Rajesh; Forman, David; Soerjomataram, Isabelle

    2015-01-01

    Background Excess body mass index (BMI) is associated with increased risk of cancer. To inform public health policyand future research, we estimated the global burden of cancer attributable to excess BMI. Methods Population attributable fractions (PAFs) were derived using relative risks and BMI estimates in adults by age, sex and country. Assuming a10-year lag-period, PAFs were calculated using BMI estimates in 2002. GLOBOCAN2012 was used to compute numbers of new cancer cases attributable to excess BMI. In an alternative scenario, we computed the proportion of potentially avoidable cancers assuming that populations maintained their BMI-level observed in 1982. Secondary analyses were performed to test the model and estimate the impactof hormone replacement therapy (HRT) and smoking. Findings Worldwide, we estimated that 481,000 or 3·6% of all new cancer cases in 2012 were attributable to excess BMI. PAFs were greater in women compared with men (5·4% versus 1·9%). The burden was concentrated in countries with very high and high human development index (HDI, PAF: 5·3% and 4·8%) compared with countries with moderate and low HDI (PAF: 1·6% and 1·0%). Corpus uteri, post-menopausal breast and colon cancers accounted for approximately two-thirds (64%) of excess BMI attributable cancers. One fourth (~118,000) of all cases related to excess BMI in 2012 could be attributed to the rising BMI since 1982. Interpretation These findings further underpin the need for a global effort to abate the rising trends in population-level excess weight. Assuming that the relationship between excess BMI and cancer is causal and the current pattern of population weight gain continues, this will likely augment the future burden of cancer. Funding World Cancer Research Fund, Marie Currie Fellowship, the National Health and Medical Research Council Australia and US NIH. PMID:25467404

  10. Interactive vs passive screen time and nighttime sleep duration among school-aged children

    PubMed Central

    Yland, Jennifer; Guan, Stanford; Emanuele, Erin; Hale, Lauren

    2016-01-01

    Background Insufficient sleep among school-aged children is a growing concern, as numerous studies have shown that chronic short sleep duration increases the risk of poor academic performance and specific adverse health outcomes. We examined the association between weekday nighttime sleep duration and 3 types of screen exposure: television, computer use, and video gaming. Methods We used age 9 data from an ethnically diverse national birth cohort study, the Fragile Families and Child Wellbeing Study, to assess the association between screen time and sleep duration among 9-year-olds, using screen time data reported by both the child (n = 3269) and by the child's primary caregiver (n= 2770). Results Within the child-reported models, children who watched more than 2 hours of television per day had shorter sleep duration by approximately 11 minutes per night compared to those who watched less than 2 hours of television (β = −0.18; P < .001). Using the caregiver-reported models, both television and computer use were associated with reduced sleep duration. For both child- and parent-reported screen time measures, we did not find statistically significant differences in effect size across various types of screen time. Conclusions Screen time from televisions and computers is associated with reduced sleep duration among 9-year-olds, using 2 sources of estimates of screen time exposure (child and parent reports). No specific type or use of screen time resulted in significantly shorter sleep duration than another, suggesting that caution should be advised against excessive use of all screens. PMID:27540566

  11. The effectiveness of a new algorithm on a three-dimensional finite element model construction of bone trabeculae in implant biomechanics.

    PubMed

    Sato, Y; Teixeira, E R; Tsuga, K; Shindoi, N

    1999-08-01

    More validity of finite element analysis (FEA) in implant biomechanics requires element downsizing. However, excess downsizing needs computer memory and calculation time. To evaluate the effectiveness of a new algorithm established for more valid FEA model construction without downsizing, three-dimensional FEA bone trabeculae models with different element sizes (300, 150 and 75 micron) were constructed. Four algorithms of stepwise (1 to 4 ranks) assignment of Young's modulus accorded with bone volume in the individual cubic element was used and then stress distribution against vertical loading was analysed. The model with 300 micron element size, with 4 ranks of Young's moduli accorded with bone volume in each element presented similar stress distribution to the model with the 75 micron element size. These results show that the new algorithm was effective, and the use of the 300 micron element for bone trabeculae representation was proposed, without critical changes in stress values and for possible savings on computer memory and calculation time in the laboratory.

  12. 29 CFR 794.123 - Method of computing annual volume of sales.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Method of computing annual volume of sales. 794.123 Section... of Sales § 794.123 Method of computing annual volume of sales. (a) Where the enterprise, during the... gross volume of sales in excess of the amount specified in the statute, it is plain that its annual...

  13. Parallel Wavefront Analysis for a 4D Interferometer

    NASA Technical Reports Server (NTRS)

    Rao, Shanti R.

    2011-01-01

    This software provides a programming interface for automating data collection with a PhaseCam interferometer from 4D Technology, and distributing the image-processing algorithm across a cluster of general-purpose computers. Multiple instances of 4Sight (4D Technology s proprietary software) run on a networked cluster of computers. Each connects to a single server (the controller) and waits for instructions. The controller directs the interferometer to several images, then assigns each image to a different computer for processing. When the image processing is finished, the server directs one of the computers to collate and combine the processed images, saving the resulting measurement in a file on a disk. The available software captures approximately 100 images and analyzes them immediately. This software separates the capture and analysis processes, so that analysis can be done at a different time and faster by running the algorithm in parallel across several processors. The PhaseCam family of interferometers can measure an optical system in milliseconds, but it takes many seconds to process the data so that it is usable. In characterizing an adaptive optics system, like the next generation of astronomical observatories, thousands of measurements are required, and the processing time quickly becomes excessive. A programming interface distributes data processing for a PhaseCam interferometer across a Windows computing cluster. A scriptable controller program coordinates data acquisition from the interferometer, storage on networked hard disks, and parallel processing. Idle time of the interferometer is minimized. This architecture is implemented in Python and JavaScript, and may be altered to fit a customer s needs.

  14. mRNA expression of dopamine receptors in peripheral blood lymphocytes of computer game addicts.

    PubMed

    Vousooghi, Nasim; Zarei, Seyed Zeinolabedin; Sadat-Shirazi, Mitra-Sadat; Eghbali, Fatemeh; Zarrindast, Mohammad Reza

    2015-10-01

    Excessive playing of computer games like some other behaviors could lead to addiction. Addictive behaviors may induce their reinforcing effects through stimulation of the brain dopaminergic mesolimbic pathway. The status of dopamine receptors in the brain may be parallel to their homologous receptors in peripheral blood lymphocytes (PBLs). Here, we have investigated the mRNA expression of dopamine D3, D4 and D5 receptors in PBLs of computer game addicts (n = 20) in comparison to normal subjects (n = 20), using a real-time PCR method. The results showed that the expression level of D3 and D4 dopamine receptors in computer game addicts were not statistically different from the control group. However, the expression of the mRNA of D5 dopamine receptor was significantly down-regulated in PBLs of computer game addicts and reached 0.42 the amount of the control group. It is concluded that unlike with drug addiction, the expression levels of the D3 and D4 dopamine receptors in computer game addicts are not altered compared to the control group. However, reduced level of the D5 dopamine receptor in computer game addicts may serve as a peripheral marker in studies where the confounding effects of abused drugs are unwanted.

  15. Understanding children's sedentary behaviour: a qualitative study of the family home environment.

    PubMed

    Granich, Joanna; Rosenberg, Michael; Knuiman, Matthew; Timperio, Anna

    2010-04-01

    Electronic media (EM) (television, electronic games and computer) use has been associated with overweight and obesity among children. Little is known about the time spent in sedentary behaviour (SB) among children within the family context. The aim of this study was to explore how the family home environment may influence children's electronic-based SB. Focus groups and family interviews were conducted with 11- to 12-year old children (n = 54) and their parents (n = 38) using a semi-structured discussion guide. Transcripts were analysed using a thematic content approach. A brief self-completed questionnaire was also used to measure leisure behaviour and electronic devices at home. Children incorporated both sedentary and physical activities into their weekly routine. Factors influencing children's EM use included parent and sibling modelling and reinforcement, personal cognitions, the physical home environment and household EM use rules and restrictions. Participants were not concerned about the excessive time children spent with EM. This under-recognition emerged as a personal influencing factor and was viewed as a major barrier to modifying children's electronic-based SB. Efforts to reduce SB in children should focus on the influencing factors that reciprocally interact within the family home. An emphasis on increasing awareness about the risks associated with spending excessive time in screen-based activities should be a priority when developing intervention strategies aimed at modifying the time children spend in SB.

  16. Determination of the excess noise of avalanche photodiodes integrated in 0.35-μm CMOS technologies

    NASA Astrophysics Data System (ADS)

    Jukić, Tomislav; Brandl, Paul; Zimmermann, Horst

    2018-04-01

    The excess noise of avalanche photodiodes (APDs) integrated in a high-voltage (HV) CMOS process and in a pin-photodiode CMOS process, both with 0.35-μm structure sizes, is described. A precise excess noise measurement technique is applied using a laser source, a spectrum analyzer, a voltage source, a current meter, a cheap transimpedance amplifier, and a personal computer with a MATLAB program. In addition, usage for on-wafer measurements is demonstrated. The measurement technique is verified with a low excess noise APD as a reference device with known ratio k = 0.01 of the impact ionization coefficients. The k-factor of an APD developed in HV CMOS is determined more accurately than known before. In addition, it is shown that the excess noise of the pin-photodiode CMOS APD depends on the optical power for avalanche gains above 35 and that modulation doping can suppress this power dependence. Modulation doping, however, increases the excess noise.

  17. On the ''excess spontaneous emission factor'' in gainguided laser amplifiers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Haus, H.A.; Kawakami, S.

    1985-01-01

    Petermann computed an ''excess spontaneous emission factor'' for gain-guided laser. In this paper, the authors investigate further the role of this factor. Such a factor also appears in the treatment of thermodynamic equilibrium in an attenuating medium-a seeming paradox. Further investigation shows that the excess spontaneous emission excitation at thermal equilibrium is cancelled by the excitations in the other modes which are correlated with that in the fundamental mode. In a medium with gain, cancellation also occurs in a short amplifier in which there is no gain discrimination among modes. The ''excess spontaneous emission factor'' is fully present only inmore » a system in which the different higher order modes have an appreciably smaller gain than the lowest order mode, a high gain amplifier. An analysis of the signal-tonoise ratio of a high gain amplifier reveals that the excess noise factor can be fully compensated by proper input excitation by a lens arrangement. The lens arrangement provides the signal with an ''excess gain'' factor. An ''excess gain'' factor is also present when a thermal source is used.« less

  18. Molecular interactions and structures in ethylene glycol-ethanol and ethylene glycol-water solutions at 303 K on densities, viscosities, and refractive indices data

    NASA Astrophysics Data System (ADS)

    Deosarkar, S. D.; Ghatbandhe, A. S.

    2014-01-01

    Molecular interactions and structural fittings in binary ethylene glycol + ethanol (EGE, x EG = 0.4111-0.0418) and ethylene glycol + water (EGW, x EG = 0.1771-0.0133) mixtures were studied through the measurement of densities (ρ), viscosities (η), and refractive indices ( n D ) at 303.15 K. Excess viscosities (η E ), molar volumes ( V m ), excess molar volumes ( V {/m E }), and molar retractions ( R M ) of the both binary systems were computed from measured properties. The measured and computed properties have been used to understand the molecular interactions in unlike solvents and structural fittings in these binary mixtures.

  19. Computer program grade 2 for the design and analysis of heat-pipe wicks

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.; Edwards, D. K.

    1976-01-01

    This user's manual describes the revised version of the computer program GRADE(1), which designs and analyzes heat pipes with graded porosity fibrous slab wicks. The revisions are: (1) automatic calculation of the minimum condenser-end stress that will not result in an excess-liquid puddle or a liquid slug in the vapor space; (2) numerical solution of the equations describing flow in the circumferential grooves to assess the burnout criterion; (3) calculation of the contribution of excess liquid in fillets and puddles to the heat-transport; (4) calculation of the effect of partial saturation on the wick performance; and (5) calculation of the effect of vapor flow, which includes viscousinertial interactions.

  20. Modeling of very low frequency (VLF) radio wave signal profile due to solar flares using the GEANT4 Monte Carlo simulation coupled with ionospheric chemistry

    NASA Astrophysics Data System (ADS)

    Palit, S.; Basak, T.; Mondal, S. K.; Pal, S.; Chakrabarti, S. K.

    2013-09-01

    X-ray photons emitted during solar flares cause ionization in the lower ionosphere (~60 to 100 km) in excess of what is expected to occur due to a quiet sun. Very low frequency (VLF) radio wave signals reflected from the D-region of the ionosphere are affected by this excess ionization. In this paper, we reproduce the deviation in VLF signal strength during solar flares by numerical modeling. We use GEANT4 Monte Carlo simulation code to compute the rate of ionization due to a M-class flare and a X-class flare. The output of the simulation is then used in a simplified ionospheric chemistry model to calculate the time variation of electron density at different altitudes in the D-region of the ionosphere. The resulting electron density variation profile is then self-consistently used in the LWPC code to obtain the time variation of the change in VLF signal. We did the modeling of the VLF signal along the NWC (Australia) to IERC/ICSP (India) propagation path and compared the results with observations. The agreement is found to be very satisfactory.

  1. Associations between Screen Time and Physical Activity among Spanish Adolescents

    PubMed Central

    Serrano-Sanchez, Jose A.; Martí-Trujillo, Sara; Lera-Navarro, Angela; Dorado-García, Cecilia; González-Henríquez, Juan J.; Sanchís-Moysi, Joaquín

    2011-01-01

    Background Excessive time in front of a single or several screens could explain a displacement of physical activity. The present study aimed at determining whether screen-time is associated with a reduced level of moderate to vigorous physical activity (MVPA) in Spanish adolescents living in favorable environmental conditions. Methodology/Principal Findings A multi-stage stratified random sampling method was used to select 3503 adolescents (12–18 years old) from the school population of Gran Canaria, Spain. MVPA, screen-time in front of television, computer, video game console and portable console was assessed in the classroom by fulfilling a standardized questionnaire. Bivariate and multivariate logistic regression analyses adjusted by a set of social-environmental variables were carried out. Forty-six percent of girls (95% CI±2.3%) and 26% of boys (95% CI±2.1%) did not meet the MVPA recommendations for adolescents. Major gender differences were observed in the time devoted to vigorous PA, video games and the total time spent on screen-based activities. Boys who reported 4 hours•week−1 or more to total screen-time showed a 64% (OR = 0.61, 95% CI, 0.44–0.86) increased risk of failing to achieve the recommended adolescent MVPA level. Participation in organized physical activities and sports competitions were more strongly associated with MVPA than screen-related behaviors. Conclusions/Significance No single screen-related behavior explained the reduction of MVPA in adolescents. However, the total time accumulated through several screen-related behaviors was negatively associated with MVPA level in boys. This association could be due to lower availability of time for exercise as the time devoted to sedentary screen-time activities increases. Participation in organized physical activities seems to counteract the negative impact of excessive time in front of screens on physical activity. PMID:21909435

  2. Associations between screen time and physical activity among Spanish adolescents.

    PubMed

    Serrano-Sanchez, Jose A; Martí-Trujillo, Sara; Lera-Navarro, Angela; Dorado-García, Cecilia; González-Henríquez, Juan J; Sanchís-Moysi, Joaquín

    2011-01-01

    Excessive time in front of a single or several screens could explain a displacement of physical activity. The present study aimed at determining whether screen-time is associated with a reduced level of moderate to vigorous physical activity (MVPA) in Spanish adolescents living in favorable environmental conditions. A multi-stage stratified random sampling method was used to select 3503 adolescents (12-18 years old) from the school population of Gran Canaria, Spain. MVPA, screen-time in front of television, computer, video game console and portable console was assessed in the classroom by fulfilling a standardized questionnaire. Bivariate and multivariate logistic regression analyses adjusted by a set of social-environmental variables were carried out. Forty-six percent of girls (95% CI±2.3%) and 26% of boys (95% CI±2.1%) did not meet the MVPA recommendations for adolescents. Major gender differences were observed in the time devoted to vigorous PA, video games and the total time spent on screen-based activities. Boys who reported 4 hours•week(-1) or more to total screen-time showed a 64% (OR = 0.61, 95% CI, 0.44-0.86) increased risk of failing to achieve the recommended adolescent MVPA level. Participation in organized physical activities and sports competitions were more strongly associated with MVPA than screen-related behaviors. No single screen-related behavior explained the reduction of MVPA in adolescents. However, the total time accumulated through several screen-related behaviors was negatively associated with MVPA level in boys. This association could be due to lower availability of time for exercise as the time devoted to sedentary screen-time activities increases. Participation in organized physical activities seems to counteract the negative impact of excessive time in front of screens on physical activity.

  3. Ultrasonic and spectral studies on charge transfer complexes of anisole and certain aromatic amines

    NASA Astrophysics Data System (ADS)

    Rajesh, R.; Raj Muhamed, R.; Justin Adaikala Baskar, A.; Kannappan, V.

    2016-10-01

    Stability constants of two complexes of anisole with aniline and N-methylaniline (NMA) are determined from the measured ultrasonic velocity in n-hexane medium at four different temperatures. Acoustic and excess thermo acoustic parameters [excess ultrasonic velocity (uE), excess molar volume (VE), excess internal pressure (πiE)] are reported for these systems at four different temperatures. The trend in acoustic and excess parameters with concentration in the two systems establishes the formation of hydrogen bonded complexes between anisole and the two amines. Thermodynamic properties are computed for the two complexes from the variation in K with temperature. The formation of these complexes is also established by UV spectral method and their spectral characteristics and stability constants are determined. K values of these complexes obtained by ultrasonic and UV spectroscopic techniques agree well. Aniline forms more stable complex than N-methylaniline with anisole in n-hexane medium.

  4. Altered cardiorespiratory coupling in young male adults with excessive online gaming.

    PubMed

    Chang, Jae Seung; Kim, Eun Young; Jung, Dooyoung; Jeong, Seong Hoon; Kim, Yeni; Roh, Myoung-Sun; Ahn, Yong Min; Hahm, Bong-Jin

    2015-09-01

    This study aimed to investigate changes in heart rate variability and cardiorespiratory coupling in male college students with problematic Internet use (PIU) excessive gaming type during action video game play to assess the relationship between PIU tendency and central autonomic regulation. Electrocardiograms and respiration were simultaneously recorded from 22 male participants with excessive online gaming and 22 controls during action video game play. Sample entropy (SampEn) was computed to assess autonomic regularity, and cross-SampEn was calculated to quantify autonomic coordination. During video game play, reduced cardiorespiratory coupling (CRC) was observed in individuals with PIU excessive gaming type compared with controls, implicating central autonomic dysregulation. The PIU tendency was associated with the severity of autonomic dysregulation. These findings indicate impaired CRC in PIU excessive gaming type, which may reflect alterations of central inhibitory control over autonomic responses to pleasurable online stimuli. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Clinical and psychological effects of excessive screen time on children.

    PubMed

    Domingues-Montanari, Sophie

    2017-04-01

    Over recent years, screen time has become a more complicated concept, with an ever-expanding variety of electronic media devices available throughout the world. Television remains the predominant type of screen-based activity among children. However, computer use, video games and ownership of devices, such as tablets and smart phones, are occurring from an increasingly young age. Screen time, in particular, television viewing, has been negatively associated with the development of physical and cognitive abilities, and positively associated with obesity, sleep problems, depression and anxiety. The physiological mechanisms that underlie the adverse health outcomes related to screen time and the relative contributions of different types of screen and media content to specific health outcomes are unclear. This review discusses the positive and negative effects of screen time on the physiological and psychological development of children. Furthermore, recommendations are offered to parents and clinicians. © 2017 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  6. CREW CHIEF: A computer graphics simulation of an aircraft maintenance technician

    NASA Technical Reports Server (NTRS)

    Aume, Nilss M.

    1990-01-01

    Approximately 35 percent of the lifetime cost of a military system is spent for maintenance. Excessive repair time is caused by not considering maintenance during design. Problems are usually discovered only after a mock-up has been constructed, when it is too late to make changes. CREW CHIEF will reduce the incidence of such problems by catching design defects in the early design stages. CREW CHIEF is a computer graphic human factors evaluation system interfaced to commercial computer aided design (CAD) systems. It creates a three dimensional man model, either male or female, large or small, with various types of clothing and in several postures. It can perform analyses for physical accessibility, strength capability with tools, visual access, and strength capability for manual materials handling. The designer would produce a drawing on his CAD system and introduce CREW CHIEF in it. CREW CHIEF's analyses would then indicate places where problems could be foreseen and corrected before the design is frozen.

  7. Optimization of ramp area aircraft push back time windows in the presence of uncertainty

    NASA Astrophysics Data System (ADS)

    Coupe, William Jeremy

    It is well known that airport surface traffic congestion at major airports is responsible for increased taxi-out times, fuel burn and excess emissions and there is potential to mitigate these negative consequences through optimizing airport surface traffic operations. Due to a highly congested voice communication channel between pilots and air traffic controllers and a data communication channel that is used only for limited functions, one of the most viable near-term strategies for improvement of the surface traffic is issuing a push back advisory to each departing aircraft. This dissertation focuses on the optimization of a push back time window for each departing aircraft. The optimization takes into account both spatial and temporal uncertainties of ramp area aircraft trajectories. The uncertainties are described by a stochastic kinematic model of aircraft trajectories, which is used to infer distributions of combinations of push back times that lead to conflict among trajectories from different gates. The model is validated and the distributions are included in the push back time window optimization. Under the assumption of a fixed taxiway spot schedule, the computed push back time windows can be integrated with a higher level taxiway scheduler to optimize the flow of traffic from the gate to the departure runway queue. To enable real-time decision making the computational time of the push back time window optimization is critical and is analyzed throughout.

  8. 75 FR 16171 - Privacy Act of 1974; Notice of Modification of Existing Computer Matching Program Between the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-31

    ... program for the purpose of income verifications and computer matching. DATES: Effective Date: The... additional verification to identify inappropriate (excess or insufficient) rental assistance, and perhaps... Act, the Native American Housing Assistance and Self-Determination Act of 1996, and the Quality...

  9. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schreck, S.; Sant, T.; Micallef, D.

    Wind turbine structures and components suffer excessive loads and premature failures when key aerodynamic phenomena are not well characterized, fail to be understood, or are inaccurately predicted. Turbine blade rotational augmentation remains incompletely characterized and understood, thus limiting robust prediction for design. Pertinent rotational augmentation research including experimental, theoretical, and computational work has been pursued for some time, but large scale wind tunnel testing is a relatively recent development for investigating wind turbine blade aerodynamics. Because of their large scale and complementary nature, the MEXICO and UAE Phase VI wind tunnel experiments offer unprecedented synergies to better characterize and understandmore » rotational augmentation of blade aerodynamics.« less

  10. Nonlinear ordinary difference equations

    NASA Technical Reports Server (NTRS)

    Caughey, T. K.

    1979-01-01

    Future space vehicles will be relatively large and flexible, and active control will be necessary to maintain geometrical configuration. While the stresses and strains in these space vehicles are not expected to be excessively large, their cumulative effects will cause significant geometrical nonlinearities to appear in the equations of motion, in addition to the nonlinearities caused by material properties. Since the only effective tool for the analysis of such large complex structures is the digital computer, it will be necessary to gain a better understanding of the nonlinear ordinary difference equations which result from the time discretization of the semidiscrete equations of motion for such structures.

  11. The effects of media on sleep.

    PubMed

    Van den Bulck, Jan

    2010-12-01

    The media are an important part of young people's lives, but television, computer games, Internet use, cellular phone use, and even book reading threaten healthy sleep. Adults do not fully comprehend the ways in which young people use various media. Media use is a type of behavior that may displace sleep time or shorten it. Media content may lead to overexcitement or cause recurring nightmares. The cellular telephone is a particular threat. Parents may also use media excessively, establishing an unhealthy environment that may lead to sleep dysfunction in children and adolescents. Therefore, anticipatory guidance for healthy behavioral changes should be focused on the family.

  12. Excess electrons in methanol clusters: Beyond the one-electron picture

    NASA Astrophysics Data System (ADS)

    Pohl, Gábor; Mones, Letif; Turi, László

    2016-10-01

    We performed a series of comparative quantum chemical calculations on various size negatively charged methanol clusters, ("separators=" CH 3 OH ) n - . The clusters are examined in their optimized geometries (n = 2-4), and in geometries taken from mixed quantum-classical molecular dynamics simulations at finite temperature (n = 2-128). These latter structures model potential electron binding sites in methanol clusters and in bulk methanol. In particular, we compute the vertical detachment energy (VDE) of an excess electron from increasing size methanol cluster anions using quantum chemical computations at various levels of theory including a one-electron pseudopotential model, several density functional theory (DFT) based methods, MP2 and coupled-cluster CCSD(T) calculations. The results suggest that at least four methanol molecules are needed to bind an excess electron on a hydrogen bonded methanol chain in a dipole bound state. Larger methanol clusters are able to form stronger interactions with an excess electron. The two simulated excess electron binding motifs in methanol clusters, interior and surface states, correlate well with distinct, experimentally found VDE tendencies with size. Interior states in a solvent cavity are stabilized significantly stronger than electron states on cluster surfaces. Although we find that all the examined quantum chemistry methods more or less overestimate the strength of the experimental excess electron stabilization, MP2, LC-BLYP, and BHandHLYP methods with diffuse basis sets provide a significantly better estimate of the VDE than traditional DFT methods (BLYP, B3LYP, X3LYP, PBE0). A comparison to the better performing many electron methods indicates that the examined one-electron pseudopotential can be reasonably used in simulations for systems of larger size.

  13. Excess electrons in methanol clusters: Beyond the one-electron picture.

    PubMed

    Pohl, Gábor; Mones, Letif; Turi, László

    2016-10-28

    We performed a series of comparative quantum chemical calculations on various size negatively charged methanol clusters, CH 3 OH n - . The clusters are examined in their optimized geometries (n = 2-4), and in geometries taken from mixed quantum-classical molecular dynamics simulations at finite temperature (n = 2-128). These latter structures model potential electron binding sites in methanol clusters and in bulk methanol. In particular, we compute the vertical detachment energy (VDE) of an excess electron from increasing size methanol cluster anions using quantum chemical computations at various levels of theory including a one-electron pseudopotential model, several density functional theory (DFT) based methods, MP2 and coupled-cluster CCSD(T) calculations. The results suggest that at least four methanol molecules are needed to bind an excess electron on a hydrogen bonded methanol chain in a dipole bound state. Larger methanol clusters are able to form stronger interactions with an excess electron. The two simulated excess electron binding motifs in methanol clusters, interior and surface states, correlate well with distinct, experimentally found VDE tendencies with size. Interior states in a solvent cavity are stabilized significantly stronger than electron states on cluster surfaces. Although we find that all the examined quantum chemistry methods more or less overestimate the strength of the experimental excess electron stabilization, MP2, LC-BLYP, and BHandHLYP methods with diffuse basis sets provide a significantly better estimate of the VDE than traditional DFT methods (BLYP, B3LYP, X3LYP, PBE0). A comparison to the better performing many electron methods indicates that the examined one-electron pseudopotential can be reasonably used in simulations for systems of larger size.

  14. A computationally identified compound antagonizes excess FGF-23 signaling in renal tubules and a mouse model of hypophosphatemia

    DOE PAGES

    Xiao, Zhousheng; Riccardi, Demian; Velazquez, Hector A.; ...

    2016-11-22

    Fibroblast growth factor–23 (FGF-23) interacts with a binary receptor complex composed of α-Klotho (α-KL) and FGF receptors (FGFRs) to regulate phosphate and vitamin D metabolism in the kidney. Excess FGF-23 production, which causes hypophosphatemia, is genetically inherited or occurs with chronic kidney disease. Among other symptoms, hypophosphatemia causes vitamin D deficiency and the bone-softening disorder rickets. Current therapeutics that target the receptor complex have limited utility clinically. In this paper, using a computationally driven, structure-based, ensemble docking and virtual high-throughput screening approach, we identified four novel compounds predicted to selectively inhibit FGF-23–induced activation of the FGFR/α-KL complex. Additional modeling andmore » functional analysis found that Zinc13407541 bound to FGF-23 and disrupted its interaction with the FGFR1/α-KL complex; experiments in a heterologous cell expression system showed that Zinc13407541 selectivity inhibited α-KL–dependent FGF-23 signaling. Zinc13407541 also inhibited FGF-23 signaling in isolated renal tubules ex vivo and partially reversed the hypophosphatemic effects of excess FGF-23 in a mouse model. Finally, these chemical probes provide a platform to develop lead compounds to treat disorders caused by excess FGF-23.« less

  15. A computationally identified compound antagonizes excess FGF-23 signaling in renal tubules and a mouse model of hypophosphatemia.

    PubMed

    Xiao, Zhousheng; Riccardi, Demian; Velazquez, Hector A; Chin, Ai L; Yates, Charles R; Carrick, Jesse D; Smith, Jeremy C; Baudry, Jerome; Quarles, L Darryl

    2016-11-22

    Fibroblast growth factor-23 (FGF-23) interacts with a binary receptor complex composed of α-Klotho (α-KL) and FGF receptors (FGFRs) to regulate phosphate and vitamin D metabolism in the kidney. Excess FGF-23 production, which causes hypophosphatemia, is genetically inherited or occurs with chronic kidney disease. Among other symptoms, hypophosphatemia causes vitamin D deficiency and the bone-softening disorder rickets. Current therapeutics that target the receptor complex have limited utility clinically. Using a computationally driven, structure-based, ensemble docking and virtual high-throughput screening approach, we identified four novel compounds predicted to selectively inhibit FGF-23-induced activation of the FGFR/α-KL complex. Additional modeling and functional analysis found that Zinc13407541 bound to FGF-23 and disrupted its interaction with the FGFR1/α-KL complex; experiments in a heterologous cell expression system showed that Zinc13407541 selectivity inhibited α-KL-dependent FGF-23 signaling. Zinc13407541 also inhibited FGF-23 signaling in isolated renal tubules ex vivo and partially reversed the hypophosphatemic effects of excess FGF-23 in a mouse model. These chemical probes provide a platform to develop lead compounds to treat disorders caused by excess FGF-23. Copyright © 2016, American Association for the Advancement of Science.

  16. A computationally identified compound antagonizes excess FGF-23 signaling in renal tubules and a mouse model of hypophosphatemia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xiao, Zhousheng; Riccardi, Demian; Velazquez, Hector A.

    Fibroblast growth factor–23 (FGF-23) interacts with a binary receptor complex composed of α-Klotho (α-KL) and FGF receptors (FGFRs) to regulate phosphate and vitamin D metabolism in the kidney. Excess FGF-23 production, which causes hypophosphatemia, is genetically inherited or occurs with chronic kidney disease. Among other symptoms, hypophosphatemia causes vitamin D deficiency and the bone-softening disorder rickets. Current therapeutics that target the receptor complex have limited utility clinically. In this paper, using a computationally driven, structure-based, ensemble docking and virtual high-throughput screening approach, we identified four novel compounds predicted to selectively inhibit FGF-23–induced activation of the FGFR/α-KL complex. Additional modeling andmore » functional analysis found that Zinc13407541 bound to FGF-23 and disrupted its interaction with the FGFR1/α-KL complex; experiments in a heterologous cell expression system showed that Zinc13407541 selectivity inhibited α-KL–dependent FGF-23 signaling. Zinc13407541 also inhibited FGF-23 signaling in isolated renal tubules ex vivo and partially reversed the hypophosphatemic effects of excess FGF-23 in a mouse model. Finally, these chemical probes provide a platform to develop lead compounds to treat disorders caused by excess FGF-23.« less

  17. Energy Savings in Cellular Networks Based on Space-Time Structure of Traffic Loads

    NASA Astrophysics Data System (ADS)

    Sun, Jingbo; Wang, Yue; Yuan, Jian; Shan, Xiuming

    Since most of energy consumed by the telecommunication infrastructure is due to the Base Transceiver Station (BTS), switching off BTSs when traffic load is low has been recognized as an effective way of saving energy. In this letter, an energy saving scheme is proposed to minimize the number of active BTSs based on the space-time structure of traffic loads as determined by principal component analysis. Compared to existing methods, our approach models traffic loads more accurately, and has a much smaller input size. As it is implemented in an off-line manner, our scheme also avoids excessive communications and computing overheads. Simulation results show that the proposed method has a comparable performance in energy savings.

  18. Investment Dynamics with Natural Expectations.

    PubMed

    Fuster, Andreas; Hebert, Benjamin; Laibson, David

    2010-01-01

    We study an investment model in which agents have the wrong beliefs about the dynamic properties of fundamentals. Specifically, we assume that agents underestimate the rate of mean reversion. The model exhibits the following six properties: (i) Beliefs are excessively optimistic in good times and excessively pessimistic in bad times. (ii) Asset prices are too volatile. (iii) Excess returns are negatively autocorrelated. (iv) High levels of corporate profits predict negative future excess returns. (v) Real economic activity is excessively volatile; the economy experiences amplified investment cycles. (vi) Corporate profits are positively autocorrelated in the short run and negatively autocorrelated in the medium run. The paper provides an illustrative model of animal spirits, amplified business cycles, and excess volatility.

  19. Investment Dynamics with Natural Expectations*

    PubMed Central

    Fuster, Andreas; Hebert, Benjamin; Laibson, David

    2012-01-01

    We study an investment model in which agents have the wrong beliefs about the dynamic properties of fundamentals. Specifically, we assume that agents underestimate the rate of mean reversion. The model exhibits the following six properties: (i) Beliefs are excessively optimistic in good times and excessively pessimistic in bad times. (ii) Asset prices are too volatile. (iii) Excess returns are negatively autocorrelated. (iv) High levels of corporate profits predict negative future excess returns. (v) Real economic activity is excessively volatile; the economy experiences amplified investment cycles. (vi) Corporate profits are positively autocorrelated in the short run and negatively autocorrelated in the medium run. The paper provides an illustrative model of animal spirits, amplified business cycles, and excess volatility. PMID:23243469

  20. Television Time among Brazilian Adolescents: Correlated Factors are Different between Boys and Girls

    PubMed Central

    Tremblay, Mark Stephen; Gonçalves, Eliane Cristina de Andrade; Silva, Roberto Jerônimo dos Santos

    2014-01-01

    Objective. The aim of this study was to identify the prevalence of excess television time and verify correlated factors in adolescent males and females. Methods. This cross-sectional study included 2,105 adolescents aged from 13 to 18 years from the city of Aracaju, Northeastern Brazil. Television time was self-reported, corresponding to the time spent watching television in a typical week. Several correlates were examined including age, skin color, socioeconomic status, parent education, physical activity level, consumption of fruits and vegetables, smoking status, alcohol use, and sports team participation. Results. The prevalence excess television time (≥2 hours/day) in girls and boys was 70.9% and 66.2%, respectively. Girls with low socioeconomic status or inadequate consumption of fruits and vegetables were more likely to have excess television time. Among boys, those >16 years of age or with black skin color were more likely to have excess television time. Conclusions. Excess television time was observed in more than two-thirds of adolescents, being more evident in girls. Correlated factors differed according to sex. Efforts to reduce television time among Brazilian adolescents, and replace with more active pursuits, may yield desirable public health benefits. PMID:24723826

  1. Automatic computational labeling of glomerular textural boundaries

    NASA Astrophysics Data System (ADS)

    Ginley, Brandon; Tomaszewski, John E.; Sarder, Pinaki

    2017-03-01

    The glomerulus, a specialized bundle of capillaries, is the blood filtering unit of the kidney. Each human kidney contains about 1 million glomeruli. Structural damages in the glomerular micro-compartments give rise to several renal conditions; most severe of which is proteinuria, where excessive blood proteins flow freely to the urine. The sole way to confirm glomerular structural damage in renal pathology is by examining histopathological or immunofluorescence stained needle biopsies under a light microscope. However, this method is extremely tedious and time consuming, and requires manual scoring on the number and volume of structures. Computational quantification of equivalent features promises to greatly ease this manual burden. The largest obstacle to computational quantification of renal tissue is the ability to recognize complex glomerular textural boundaries automatically. Here we present a computational pipeline to accurately identify glomerular boundaries with high precision and accuracy. The computational pipeline employs an integrated approach composed of Gabor filtering, Gaussian blurring, statistical F-testing, and distance transform, and performs significantly better than standard Gabor based textural segmentation method. Our integrated approach provides mean accuracy/precision of 0.89/0.97 on n = 200Hematoxylin and Eosin (HE) glomerulus images, and mean 0.88/0.94 accuracy/precision on n = 200 Periodic Acid Schiff (PAS) glomerulus images. Respective accuracy/precision of the Gabor filter bank based method is 0.83/0.84 for HE and 0.78/0.8 for PAS. Our method will simplify computational partitioning of glomerular micro-compartments hidden within dense textural boundaries. Automatic quantification of glomeruli will streamline structural analysis in clinic, and can help realize real time diagnoses and interventions.

  2. Radiation-induced skin carcinomas of the head and neck

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ron, E.; Modan, B.; Preston, D.

    1991-03-01

    Radiation exposures to the scalp during childhood for tinea capitis were associated with a fourfold increase in skin cancer, primarily basal cell carcinomas, and a threefold increase in benign skin tumors. Malignant melanoma, however, was not significantly elevated. Overall, 80 neoplasms were identified from an extensive search of the pathology logs of all major hospitals in Israel and computer linkage with the national cancer registry. Radiation dose to the scalp was computed for over 10,000 persons irradiated for ringworm (mean 7 Gy), and incidence rates were contrasted with those observed in 16,000 matched comparison subjects. The relative risk of radiogenicmore » skin cancer did not differ significantly between men or women or by time since exposure; however, risk was greatest following exposures in early childhood. After adjusting for sex, ethnic origin, and attained age, the estimated excess relative risk was 0.7 per Gy and the average excess risk over the current follow-up was 0.31/10(4) PY-Gy. The risk per Gy of radiation-induced skin cancer was intermediate between the high risk found among whites and no risk found among blacks in a similar study conducted in New York City. This finding suggests the role that subsequent exposure to uv radiation likely plays in the expression of a potential radiation-induced skin malignancy.« less

  3. Excessive loss of skeletal muscle mass in older adults with type 2 diabetes.

    PubMed

    Park, Seok Won; Goodpaster, Bret H; Lee, Jung Sun; Kuller, Lewis H; Boudreau, Robert; de Rekeneire, Nathalie; Harris, Tamara B; Kritchevsky, Stephen; Tylavsky, Frances A; Nevitt, Michael; Cho, Yong-wook; Newman, Anne B

    2009-11-01

    A loss of skeletal muscle mass is frequently observed in older adults. The aim of the study was to investigate the impact of type 2 diabetes on the changes in body composition, with particular interest in the skeletal muscle mass. We examined total body composition with dual-energy X-ray absorptiometry annually for 6 years in 2,675 older adults. We also measured mid-thigh muscle cross-sectional area (CSA) with computed tomography in year 1 and year 6. At baseline, 75-g oral glucose challenge tests were performed. Diagnosed diabetes (n = 402, 15.0%) was identified by self-report or use of hypoglycemic agents. Undiagnosed diabetes (n = 226, 8.4%) was defined by fasting plasma glucose (>or=7 mmol/l) or 2-h postchallenge plasma glucose (>or=11.1 mmol/l). Longitudinal regression models were fit to examine the effect of diabetes on the changes in body composition variables. Older adults with either diagnosed or undiagnosed type 2 diabetes showed excessive loss of appendicular lean mass and trunk fat mass compared with nondiabetic subjects. Thigh muscle CSA declined two times faster in older women with diabetes than their nondiabetic counterparts. These findings remained significant after adjusting for age, sex, race, clinic site, baseline BMI, weight change intention, and actual weight changes over time. Type 2 diabetes is associated with excessive loss of skeletal muscle and trunk fat mass in community-dwelling older adults. Older women with type 2 diabetes are at especially high risk for loss of skeletal muscle mass.

  4. Ultrafast dynamics of liquid water: Energy relaxation and transfer processes of the OH stretch and the HOH bend

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Imoto, Sho; Xantheas, Sotiris S.; Saito, Shinji

    2015-08-27

    The vibrational energy relaxation and transfer processes of the OH stretching and the HOH bending vibrations in liquid water are investigated via the theoretical calculation of the pump-probe spectra obtained from non-equilibrium molecular dynamics simulations with the TTM3-F interaction potential. The excitation of the OH stretch induces an instantaneous response of the high frequency librational motions in the 600-1000 cm-1 range. In addition, the excess energy of the OH stretch of a water molecule quickly transfers to the OH stretches of molecules in its first hydration shell with a time constant of ~50 fs, followed by relaxation to the HOHmore » bends of the surrounding molecules with a time constant of 230 fs. The excitation of the HOH bend also results in the ultrafast excitation of the high frequency librational motions. The energy of the excited HOH bend of a water molecule decays, with a time constant of 200 fs, mainly to the relaxation of the HOH bends of its surrounding molecules. The energies of the HOH bends were found to transfer quickly to the intermolecular motions via the coupling with the high frequency librational motions. The excess energy of the OH stretch or the HOH bend relaxes to the high frequency intermolecular librational motions and eventually to the hot ground state with a time scale of ~1 ps via the coupling with the librational and translational motions. The energy relaxation and transfer processes were found to depend on the local hydrogen bonding network; the relaxations of the excess energy of the OH stretch and the HOH bend of four- and five-coordinated molecules are faster than those of a three-coordinated molecule due to the delocalization of the vibrational motions of the former (four- and five-coordinated molecules) compared to those of the later (three-coordinated molecules). The present results highlight the importance of the high frequency intermolecular librational modes in facilitating the ultrafast energy relaxation process in liquid water via their strong nonlinear couplings with the intramolecular OH stretching and HOH bending vibrations. S.S.X. acknowledges the support of the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle. The calculation was carried out using the computing resources at the Research Center for Computational Science in Okazaki, Japan.« less

  5. Is Excessive Polypharmacy a Transient or Persistent Phenomenon? A Nationwide Cohort Study in Taiwan

    PubMed Central

    Wang, Yi-Jen; Chiang, Shu-Chiung; Lee, Pei-Chen; Chen, Yu-Chun; Chou, Li-Fang; Chou, Yueh-Ching; Chen, Tzeng-Ji

    2018-01-01

    Objectives: Target populations with persistent polypharmacy should be identified prior to implementing strategies against inappropriate medication use, yet limited information regarding such populations is available. The main objectives were to explore the trends of excessive polypharmacy, whether transient or persistent, at the individual level. The secondary objectives were to identify the factors associated with persistently excessive polypharmacy and to estimate the probabilities for repeatedly excessive polypharmacy. Methods: Retrospective cohort analyses of excessive polypharmacy, defined as prescription of ≥ 10 medicines at an ambulatory visit, from 2001 to 2013 were conducted using a nationally representative claims database in Taiwan. Survival analyses with log-rank test of adult patients with first-time excessive polypharmacy were conducted to predict the probabilities, stratified by age and sex, of having repeatedly excessive polypharmacy. Results: During the study period, excessive polypharmacy occurred in 5.4% of patients for the first time. Among them, 63.9% had repeatedly excessive polypharmacy and the probabilities were higher in men and old people. Men versus women, and old versus middle-aged and young people had shorter median excessive polypharmacy-free times (9.4 vs. 5.5 months, 5.3 vs. 10.1 and 35.0 months, both p < 0.001). Overall, the probabilities of having no repeatedly excessive polypharmacy within 3 months, 6 months, and 1 year were 59.9, 53.6, and 48.1%, respectively. Conclusion: Although male and old patients were more likely to have persistently excessive polypharmacy, most cases of excessive polypharmacy were transient or did not re-appear in the short run. Systemic deprescribing measures should be tailored to at-risk groups. PMID:29515446

  6. Range indices of geomagnetic activity

    USGS Publications Warehouse

    Stuart, W.F.; Green, A.W.

    1988-01-01

    The simplest index of geomagnetic activity is the range in nT from maximum to minimum value of the field in a given time interval. The hourly range R was recommended by IAGA for use at observatories at latitudes greater than 65??, but was superceded by AE. The most used geomagnetic index K is based on the range of activity in a 3 h interval corrected for the regular daily variation. In order to take advantage of real time data processing, now available at many observatories, it is proposed to introduce a 1 h range index and also a 3 h range index. Both will be computed hourly, i.e. each will have a series of 24 per day, the 3 h values overlapping. The new data will be available as the range (R) of activity in nT and also as a logarithmic index (I) of the range. The exponent relating index to range in nT is based closely on the scale used for computing K values. The new ranges and range indices are available, from June 1987, to users in real time and can be accessed by telephone connection or computer network. Their first year of production is regarded as a trial period during which their value to the scientific and commercial communities will be assessed, together with their potential as indicators of regional and global disturbances' and in which trials will be conducted into ways of eliminating excessive bias at quiet times due to the rate of change of the daily variation field. ?? 1988.

  7. Effective recombination coefficient and solar zenith angle effects on low-latitude D-region ionosphere evaluated from VLF signal amplitude and its time delay during X-ray solar flares

    NASA Astrophysics Data System (ADS)

    Basak, Tamal; Chakrabarti, Sandip Kumar

    Excess solar X-ray radiation during solar flares causes an enhancement of ionization in the ionospheric D-region and hence affects sub-ionospherically propagating VLF signal amplitude and phase. VLF signal amplitude perturbation (DeltaA) and amplitude time delay (Deltat) (vis- ´a-vis corresponding X-ray light curve as measured by GOES-15) of NWC/19.8 kHz signal have been computed for solar flares which is detected by us during Jan-Sep 2011. The signal is recorded by SoftPAL facility of IERC/ICSP, Sitapur (22(°) 27'N, 87(°) 45'E), West Bengal, India. In first part of the work, using the well known LWPC technique, we simulated the flare induced excess lower ionospheric electron density by amplitude perturbation method. Unperturbed D-region electron density is also obtained from simulation and compared with IRI-model results. Using these simulation results and time delay as key parameters, we calculate the effective electron recombination coefficient (alpha_{eff}) at solar flare peak region. Our results match with the same obtained by other established models. In the second part, we dealt with the solar zenith angle effect on D-region during flares. We relate this VLF data with the solar X-ray data. We find that the peak of the VLF amplitude occurs later than the time of the X-ray peak for each flare. We investigate this so-called time delay (Deltat). For the C-class flares we find that there is a direct correspondence between Deltat of a solar flare and the average solar zenith angle Z over the signal propagation path at flare occurrence time. Now for deeper analysis, we compute the Deltat for different local diurnal time slots DT. We find that while the time delay is anti-correlated with the flare peak energy flux phi_{max} independent of these time slots, the goodness of fit, as measured by reduced-chi(2) , actually worsens as the day progresses. The variation of the Z dependence of reduced-chi(2) seems to follow the variation of standard deviation of Z along the T_x-R_x propagation path. In other words, for the flares having almost constant Z over the path a tighter anti-correlation between Deltat and phi_{max} was observed.

  8. Effective recombination coefficient and solar zenith angle effects on low-latitude D-region ionosphere evaluated from VLF signal amplitude and its time delay during X-ray solar flares

    NASA Astrophysics Data System (ADS)

    Basak, Tamal; Chakrabarti, Sandip K.

    2013-12-01

    Excess solar X-ray radiation during solar flares causes an enhancement of ionization in the ionospheric D-region and hence affects sub-ionospherically propagating VLF signal amplitude and phase. VLF signal amplitude perturbation (Δ A) and amplitude time delay (Δ t) (vis-á-vis corresponding X-ray light curve as measured by GOES-15) of NWC/19.8 kHz signal have been computed for solar flares which is detected by us during Jan-Sep 2011. The signal is recorded by SoftPAL facility of IERC/ICSP, Sitapur (22∘ 27'N, 87∘ 45'E), West Bengal, India. In first part of the work, using the well known LWPC technique, we simulated the flare induced excess lower ionospheric electron density by amplitude perturbation method. Unperturbed D-region electron density is also obtained from simulation and compared with IRI-model results. Using these simulation results and time delay as key parameters, we calculate the effective electron recombination coefficient ( α eff ) at solar flare peak region. Our results match with the same obtained by other established models. In the second part, we dealt with the solar zenith angle effect on D-region during flares. We relate this VLF data with the solar X-ray data. We find that the peak of the VLF amplitude occurs later than the time of the X-ray peak for each flare. We investigate this so-called time delay (Δ t). For the C-class flares we find that there is a direct correspondence between Δ t of a solar flare and the average solar zenith angle Z over the signal propagation path at flare occurrence time. Now for deeper analysis, we compute the Δ t for different local diurnal time slots DT. We find that while the time delay is anti-correlated with the flare peak energy flux ϕ max independent of these time slots, the goodness of fit, as measured by reduced- χ 2, actually worsens as the day progresses. The variation of the Z dependence of reduced- χ 2 seems to follow the variation of standard deviation of Z along the T x - R x propagation path. In other words, for the flares having almost constant Z over the path a tighter anti-correlation between Δ t and ϕ max was observed.

  9. Measuring excess free energies of self-assembled membrane structures.

    PubMed

    Norizoe, Yuki; Daoulas, Kostas Ch; Müller, Marcus

    2010-01-01

    Using computer simulation of a solvent-free, coarse-grained model for amphiphilic membranes, we study the excess free energy of hourglass-shaped connections (i.e., stalks) between two apposed bilayer membranes. In order to calculate the free energy by simulation in the canonical ensemble, we reversibly transfer two apposed bilayers into a configuration with a stalk in three steps. First, we gradually replace the intermolecular interactions by an external, ordering field. The latter is chosen such that the structure of the non-interacting system in this field closely resembles the structure of the original, interacting system in the absence of the external field. The absence of structural changes along this path suggests that it is reversible; a fact which is confirmed by expanded-ensemble simulations. Second, the external, ordering field is changed as to transform the non-interacting system from the apposed bilayer structure to two-bilayers connected by a stalk. The final external field is chosen such that the structure of the non-interacting system resembles the structure of the stalk in the interacting system without a field. On the third branch of the transformation path, we reversibly replace the external, ordering field by non-bonded interactions. Using expanded-ensemble techniques, the free energy change along this reversible path can be obtained with an accuracy of 10(-3)k(B)T per molecule in the n VT-ensemble. Calculating the chemical potential, we obtain the free energy of a stalk in the grandcanonical ensemble, and employing semi-grandcanonical techniques, we calculate the change of the excess free energy upon altering the molecular architecture. This computational strategy can be applied to compute the free energy of self-assembled phases in lipid and copolymer systems, and the excess free energy of defects or interfaces.

  10. Availability and night-time use of electronic entertainment and communication devices are associated with short sleep duration and obesity among Canadian children.

    PubMed

    Chahal, H; Fung, C; Kuhle, S; Veugelers, P J

    2013-02-01

    What is already known about this subject Short sleep duration is a risk factor for obesity. Television (TV) in the bedroom has been shown to be associated with excess body weight in children. Children increasingly use other electronic entertainment and communication devices (EECDs) such as video games, computers, and smart phones. What this study adds Access to and night-time use of EECDs are associated with shortened sleep duration, excess body weight, poorer diet quality, and lower physical activity levels. Our findings reinforce existing recommendations pertaining to TV and Internet access by the American Academy of Pediatrics and suggest to have these expanded to restricted availability of video games and smart phones in children's bedrooms. While the prevalence of childhood obesity and access to and use of electronic entertainment and communication devices (EECDs) have increased in the past decades, no earlier study has examined their interrelationship. To examine whether night-time access to and use of EECDs are associated with sleep duration, body weights, diet quality, and physical activity of Canadian children. A representative sample of 3398 grade 5 children in Alberta, Canada, was surveyed. The survey included questions on children's lifestyles and health behaviours, the Harvard Youth/Adolescent Food Frequency questionnaire, a validated questionnaire on physical activity, and measurements of heights and weights. Random effect models were used to assess the associations of night-time access to and use of EECDs with sleep, diet quality, physical activity, and body weights. Sixty-four percent of parents reported that their child had access to one or more EECDs in their bedroom. Access to and night-time use of EECDs were associated with shortened sleep duration, excess body weight, poorer diet quality, and lower physical activity levels in a statistically significant manner. Limiting the availability of EECDs in children's bedrooms and discouraging their night-time use may be considered as a strategy to promote sleep and reduce childhood obesity. © 2012 The Authors. Pediatric Obesity © 2012 International Association for the Study of Obesity.

  11. 41 CFR 102-36.135 - How much time do we have to pick up excess personal property that has been approved for transfer?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Excess Personal Property For Our Agency Processing Transfers § 102-36.135 How much time do we have to... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false How much time do we have to pick up excess personal property that has been approved for transfer? 102-36.135 Section 102-36...

  12. 41 CFR 102-36.135 - How much time do we have to pick up excess personal property that has been approved for transfer?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Excess Personal Property For Our Agency Processing Transfers § 102-36.135 How much time do we have to... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false How much time do we have to pick up excess personal property that has been approved for transfer? 102-36.135 Section 102-36...

  13. 41 CFR 102-36.135 - How much time do we have to pick up excess personal property that has been approved for transfer?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Excess Personal Property For Our Agency Processing Transfers § 102-36.135 How much time do we have to... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false How much time do we have to pick up excess personal property that has been approved for transfer? 102-36.135 Section 102-36...

  14. 41 CFR 102-36.135 - How much time do we have to pick up excess personal property that has been approved for transfer?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Excess Personal Property For Our Agency Processing Transfers § 102-36.135 How much time do we have to... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false How much time do we have to pick up excess personal property that has been approved for transfer? 102-36.135 Section 102-36...

  15. 41 CFR 102-36.135 - How much time do we have to pick up excess personal property that has been approved for transfer?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Excess Personal Property For Our Agency Processing Transfers § 102-36.135 How much time do we have to... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false How much time do we have to pick up excess personal property that has been approved for transfer? 102-36.135 Section 102-36...

  16. Standard Period Life Table Used to Compute the Life Expectancy of Diseased Subpopulations: More Confusing Than Helpful.

    PubMed

    Perron, Linda; Simard, Marc; Brisson, Jacques; Hamel, Denis; Lo, Ernest

    2017-10-01

    Life expectancy (LE) based on a period life table (PLT) traditionally serves as a general population summary metric. It is, however, becoming more frequently reported for chronically afflicted subpopulations. In general populations, there is always an obvious real cohort sharing the hypothetical PLT cohort characteristics, and the LE estimate is intuitively understood as that real cohort mean survival time, assuming constancy of death risks. In diseased subpopulations, the correspondence between the hypothetical cohort and a real cohort is not straightforward. Furthermore, the excess mortality of chronic diseases usually changes according to age at onset and time since onset. The standard PLT method does not allow for proper control of these issues, so the LE estimate can only be deemed valid under specific assumptions. Without clear statements about the real cohort to whom the estimate is intended and the assumptions allowing disregard of the effect of age at onset and time since onset, LEs of afflicted subpopulations computed with the PLT are only abstract numbers summarizing mortality rates. If called "life expectancy," they can be seriously misleading. The same applies to health-adjusted LE.

  17. Joint probabilities of extreme precipitation and wind gusts in Germany

    NASA Astrophysics Data System (ADS)

    von Waldow, H.; Martius, O.

    2012-04-01

    Extreme meteorological events such as storms, heavy rain, floods, droughts and heat waves can have devastating consequences for human health, infrastructure and ecosystems. Concomitantly occurring extreme events might interact synergistically to produce a particularly hazardous impact. The joint occurrence of droughts and heat waves, for example, can have a very different impact on human health and ecosystems both in quantity and quality, than just one of the two extreme events. The co-occurrence of certain types of extreme events is plausible from physical and dynamical considerations, for example heavy precipitation and high wind speeds in the pathway of strong extratropical cyclones. The winter storm Kyrill not only caused wind gust speeds well in excess of 30 m/s across Europe, but also brought 24 h precipitation sums greater than the mean January accumulations in some regions. However, the existence of such compound risks is currently not accounted for by insurance companies, who assume independence of extreme weather events to calculate their premiums. While there are established statistical methods to model the extremes of univariate meteorological variables, the modelling of multidimensional extremes calls for an approach that is tailored to the specific problem at hand. A first step involves defining extreme bivariate wind/precipitation events. Because precipitation and wind gusts caused by the same cyclone or convective cell do not occur at exactly the same location and at the same time, it is necessary to find a sound definition of "extreme compound event" for this case. We present a data driven method to choose appropriate time and space intervals that define "concomitance" for wind and precipitation extremes. Based on station data of wind speed and gridded precipitation data, we arrive at time and space intervals that compare well with the typical time and space scales of extratropical cyclones, i.e. a maximum time lag of 1 day and a maximum distance of about 300 km between associated wind and rain events. After modelling extreme precipitation and wind separately, we explore the practicability of characterising their joint distribution using a bivariate threshold excess model. In particular, we present different dependence measures and report about the computational feasibility and available computer codes.

  18. Excess thermodynamics of mixtures involving xenon and light linear alkanes by computer simulation.

    PubMed

    Carvalho, A J Palace; Ramalho, J P Prates; Martins, Luís F G

    2007-06-14

    Excess molar enthalpies and excess molar volumes as a function of composition for liquid mixtures of xenon + ethane (at 161.40 K), xenon + propane (at 161.40 K) and xenon + n-butane (at 182.34 K) have been obtained by Monte Carlo computer simulations and compared with available experimental data. Simulation conditions were chosen to closely match those of the corresponding experimental results. The TraPPE-UA force field was selected among other force fields to model all the alkanes studied, whereas the one-center Lennard-Jones potential from Bohn et al. was used for xenon. The calculated H(m)(E) and V(m)(E) for all systems are negative, increasing in magnitude as the alkane chain length increases. The results for these systems were compared with experimental data and with other theoretical calculations using the SAFT approach. An excellent agreement between simulation and experimental results was found for xenon + ethane system, whereas for the remaining two systems, some deviations that become progressively more significant as the alkane chain length increases were observed.

  19. High performance GPU processing for inversion using uniform grid searches

    NASA Astrophysics Data System (ADS)

    Venetis, Ioannis E.; Saltogianni, Vasso; Stiros, Stathis; Gallopoulos, Efstratios

    2017-04-01

    Many geophysical problems are described by systems of redundant, highly non-linear systems of ordinary equations with constant terms deriving from measurements and hence representing stochastic variables. Solution (inversion) of such problems is based on numerical, optimization methods, based on Monte Carlo sampling or on exhaustive searches in cases of two or even three "free" unknown variables. Recently the TOPological INVersion (TOPINV) algorithm, a grid search-based technique in the Rn space, has been proposed. TOPINV is not based on the minimization of a certain cost function and involves only forward computations, hence avoiding computational errors. The basic concept is to transform observation equations into inequalities on the basis of an optimization parameter k and of their standard errors, and through repeated "scans" of n-dimensional search grids for decreasing values of k to identify the optimal clusters of gridpoints which satisfy observation inequalities and by definition contain the "true" solution. Stochastic optimal solutions and their variance-covariance matrices are then computed as first and second statistical moments. Such exhaustive uniform searches produce an excessive computational load and are extremely time consuming for common computers based on a CPU. An alternative is to use a computing platform based on a GPU, which nowadays is affordable to the research community, which provides a much higher computing performance. Using the CUDA programming language to implement TOPINV allows the investigation of the attained speedup in execution time on such a high performance platform. Based on synthetic data we compared the execution time required for two typical geophysical problems, modeling magma sources and seismic faults, described with up to 18 unknown variables, on both CPU/FORTRAN and GPU/CUDA platforms. The same problems for several different sizes of search grids (up to 1012 gridpoints) and numbers of unknown variables were solved on both platforms, and execution time as a function of the grid dimension for each problem was recorded. Results indicate an average speedup in calculations by a factor of 100 on the GPU platform; for example problems with 1012 grid-points require less than two hours instead of several days on conventional desktop computers. Such a speedup encourages the application of TOPINV on high performance platforms, as a GPU, in cases where nearly real time decisions are necessary, for example finite fault modeling to identify possible tsunami sources.

  20. Step free energies at faceted solid surfaces: Theory and atomistic calculations for steps on the Cu(111) surface

    NASA Astrophysics Data System (ADS)

    Freitas, Rodrigo; Frolov, Timofey; Asta, Mark

    2017-04-01

    A theory for the thermodynamic properties of steps on faceted crystalline surfaces is presented. The formalism leads to the definition of step excess quantities, including an excess step stress that is the step analogy of surface stress. The approach is used to develop a relationship between the temperature dependence of the step free energy (γst) and step excess quantities for energy and stress that can be readily calculated by atomistic simulations. We demonstrate the application of this formalism in thermodynamic-integration (TI) calculations of the step free energy, based on molecular-dynamics simulations, considering <110 > steps on the {111 } surface of a classical potential model for elemental Cu. In this application we employ the Frenkel-Ladd approach to compute the reference value of γst for the TI calculations. Calculated results for excess energy and stress show relatively weak temperature dependencies up to a homologous temperature of approximately 0.6, above which these quantities increase strongly and the step stress becomes more isotropic. From the calculated excess quantities we compute γst over the temperature range from zero up to the melting point (Tm). We find that γst remains finite up to Tm, indicating the absence of a roughening temperature for this {111 } surface facet, but decreases by roughly fifty percent from the zero-temperature value. The strongest temperature dependence occurs above homologous temperatures of approximately 0.6, where the step becomes configurationally disordered due to the formation of point defects and appreciable capillary fluctuations.

  1. The influence of fuel type to combustion characteristic in diffusion flame drying by computational fluid dynamics simulation

    NASA Astrophysics Data System (ADS)

    Septiani, Eka Lutfi; Widiyastuti, W.; Machmudah, Siti; Nurtono, Tantular; Winardi, Sugeng

    2017-05-01

    Diffusion flame spray drying has become promising method in nanoparticles synthesis giving several advantages and low operation cost. In order to scale up the process which needs high experimentation time and cost, Computational Fluid Dynamics (CFD) by Ansys Fluent 15.0 software has been used. Combustion characteristic in diffusion flame reactor may affects particle size distribution. This study aims to observe influence of fuel type to combustion characteristic in the reactor. Large Eddy Simulation (LES) and non-premixed combustion model are selected for the turbulence and combustion model respectively. Methane, propane, and LPG in 0.5 L/min were used as type of fuel. While the oxidizer is air with 200% excess of O2. Simulation result shown that the maximum temperature was obtained from propane-air combustion in 2268 K. However, the stable temperature contour was achieved by methane-air combustion.

  2. Automatic finite element generators

    NASA Technical Reports Server (NTRS)

    Wang, P. S.

    1984-01-01

    The design and implementation of a software system for generating finite elements and related computations are described. Exact symbolic computational techniques are employed to derive strain-displacement matrices and element stiffness matrices. Methods for dealing with the excessive growth of symbolic expressions are discussed. Automatic FORTRAN code generation is described with emphasis on improving the efficiency of the resultant code.

  3. PsbS is required for systemic acquired acclimation and post-excess-light-stress optimization of chlorophyll fluorescence decay times in Arabidopsis

    PubMed Central

    Ciszak, Kamil; Kulasek, Milena; Barczak, Anna; Grzelak, Justyna; Maćkowski, Sebastian; Karpiński, Stanisław

    2015-01-01

    Systemic acquired acclimation (SAA) is an important light acclimatory mechanism that depends on the global adjustments of non-photochemical quenching and chloroplast retrograde signaling. As the exact regulation of these processes is not known, we measured time-resolved fluorescence of chlorophyll a in Arabidopsis thaliana leaves exposed to excess light, in leaves undergoing SAA, and in leaves after excess light episode. We compare the behavior induced in wild-type plants with null mutant of non-photochemical quenching (npq4–1). The wild type rosettes exhibit a small reduction of fluorescence decay times in leaves directly exposed to excess light and in leaves undergoing SAA in ambient low light. However in npq4–1 exposition to excess light results in much faster fluorescence decay, which is insensitive to excitation power. At the same time npq4–1 leaves undergoing SAA displayed intermediate fluorescence decay. The npq4–1 plants also lost the ability to optimize florescence decay, and thus chlorophyll a dynamics up to 2 h after excess light episode. The fluorescence decay dynamics in both WT and npq4–1 can be described by a set of 3 maximum decay times. Based on the results, we concluded that functional PsbS is required for optimization of absorbed photon fate and optimal light acclimatory responses such as SAA or after excess light stress. PMID:25654166

  4. Simulation of solid-liquid flows in a stirred bead mill based on computational fluid dynamics (CFD)

    NASA Astrophysics Data System (ADS)

    Winardi, S.; Widiyastuti, W.; Septiani, E. L.; Nurtono, T.

    2018-05-01

    The selection of simulation model is an important step in computational fluid dynamics (CFD) to obtain an agreement with experimental work. In addition, computational time and processor speed also influence the performance of the simulation results. Here, we report the simulation of solid-liquid flow in a bead mill using Eulerian model. Multiple Reference Frame (MRF) was also used to model the interaction between moving (shaft and disk) and stationary (chamber exclude shaft and disk) zones. Bead mill dimension was based on the experimental work of Yamada and Sakai (2013). The effect of shaft rotation speed of 1200 and 1800 rpm on the particle distribution and the flow field was discussed. For rotation speed of 1200 rpm, the particles spread evenly throughout the bead mill chamber. On the other hand, for the rotation speed of 1800 rpm, the particles tend to be thrown to the near wall region resulting in the dead zone and found no particle in the center region. The selected model agreed well to the experimental data with average discrepancies less than 10%. Furthermore, the simulation was run without excessive computational cost.

  5. An accessible method for implementing hierarchical models with spatio-temporal abundance data

    USGS Publications Warehouse

    Ross, Beth E.; Hooten, Melvin B.; Koons, David N.

    2012-01-01

    A common goal in ecology and wildlife management is to determine the causes of variation in population dynamics over long periods of time and across large spatial scales. Many assumptions must nevertheless be overcome to make appropriate inference about spatio-temporal variation in population dynamics, such as autocorrelation among data points, excess zeros, and observation error in count data. To address these issues, many scientists and statisticians have recommended the use of Bayesian hierarchical models. Unfortunately, hierarchical statistical models remain somewhat difficult to use because of the necessary quantitative background needed to implement them, or because of the computational demands of using Markov Chain Monte Carlo algorithms to estimate parameters. Fortunately, new tools have recently been developed that make it more feasible for wildlife biologists to fit sophisticated hierarchical Bayesian models (i.e., Integrated Nested Laplace Approximation, ‘INLA’). We present a case study using two important game species in North America, the lesser and greater scaup, to demonstrate how INLA can be used to estimate the parameters in a hierarchical model that decouples observation error from process variation, and accounts for unknown sources of excess zeros as well as spatial and temporal dependence in the data. Ultimately, our goal was to make unbiased inference about spatial variation in population trends over time.

  6. A novel approach to estimate emissions from large transportation networks: Hierarchical clustering-based link-driving-schedules for EPA-MOVES using dynamic time warping measures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aziz, H. M. Abdul; Ukkusuri, Satish V.

    We present that EPA-MOVES (Motor Vehicle Emission Simulator) is often integrated with traffic simulators to assess emission levels of large-scale urban networks with signalized intersections. High variations in speed profiles exist in the context of congested urban networks with signalized intersections. The traditional average-speed-based emission estimation technique with EPA-MOVES provides faster execution while underestimates the emissions in most cases because of ignoring the speed variation at congested networks with signalized intersections. In contrast, the atomic second-by-second speed profile (i.e., the trajectory of each vehicle)-based technique provides accurate emissions at the cost of excessive computational power and time. We addressed thismore » issue by developing a novel method to determine the link-driving-schedules (LDSs) for the EPA-MOVES tool. Our research developed a hierarchical clustering technique with dynamic time warping similarity measures (HC-DTW) to find the LDS for EPA-MOVES that is capable of producing emission estimates better than the average-speed-based technique with execution time faster than the atomic speed profile approach. We applied the HC-DTW on a sample data from a signalized corridor and found that HC-DTW can significantly reduce computational time without compromising the accuracy. The developed technique in this research can substantially contribute to the EPA-MOVES-based emission estimation process for large-scale urban transportation network by reducing the computational time with reasonably accurate estimates. This method is highly appropriate for transportation networks with higher variation in speed such as signalized intersections. Lastly, experimental results show error difference ranging from 2% to 8% for most pollutants except PM 10.« less

  7. A novel approach to estimate emissions from large transportation networks: Hierarchical clustering-based link-driving-schedules for EPA-MOVES using dynamic time warping measures

    DOE PAGES

    Aziz, H. M. Abdul; Ukkusuri, Satish V.

    2017-06-29

    We present that EPA-MOVES (Motor Vehicle Emission Simulator) is often integrated with traffic simulators to assess emission levels of large-scale urban networks with signalized intersections. High variations in speed profiles exist in the context of congested urban networks with signalized intersections. The traditional average-speed-based emission estimation technique with EPA-MOVES provides faster execution while underestimates the emissions in most cases because of ignoring the speed variation at congested networks with signalized intersections. In contrast, the atomic second-by-second speed profile (i.e., the trajectory of each vehicle)-based technique provides accurate emissions at the cost of excessive computational power and time. We addressed thismore » issue by developing a novel method to determine the link-driving-schedules (LDSs) for the EPA-MOVES tool. Our research developed a hierarchical clustering technique with dynamic time warping similarity measures (HC-DTW) to find the LDS for EPA-MOVES that is capable of producing emission estimates better than the average-speed-based technique with execution time faster than the atomic speed profile approach. We applied the HC-DTW on a sample data from a signalized corridor and found that HC-DTW can significantly reduce computational time without compromising the accuracy. The developed technique in this research can substantially contribute to the EPA-MOVES-based emission estimation process for large-scale urban transportation network by reducing the computational time with reasonably accurate estimates. This method is highly appropriate for transportation networks with higher variation in speed such as signalized intersections. Lastly, experimental results show error difference ranging from 2% to 8% for most pollutants except PM 10.« less

  8. [Computer games and Internet addiction as well as pathological gambling. Therapy approaches].

    PubMed

    Wölfling, K; Leménager, T; Peukert, P; Batra, A

    2013-05-01

    In accordance with the development of substance-related disorders, behavioral addictions, such as internet use disorder and pathological gambling are regarded as repetitive excessive behavior which increasingly turns into an automatic action which is difficult to control intentionally. This automatic behavior is reinforced by learning processes, associated with neuroadaption, especially in the dopaminergic reward system. Treatment aims at finding alternatives for gambling or online activities and reducing times online so that social contacts need to be re-established. The following article provides a short overview on studies assessing the effects of different psychotherapeutic and pharmacological interventions and details psychotherapeutic treatment options.

  9. Cold dark matter confronts the cosmic microwave background - Large-angular-scale anisotropies in Omega sub 0 + lambda 1 models

    NASA Technical Reports Server (NTRS)

    Gorski, Krzysztof M.; Silk, Joseph; Vittorio, Nicola

    1992-01-01

    A new technique is used to compute the correlation function for large-angle cosmic microwave background anisotropies resulting from both the space and time variations in the gravitational potential in flat, vacuum-dominated, cold dark matter cosmological models. Such models with Omega sub 0 of about 0.2, fit the excess power, relative to the standard cold dark matter model, observed in the large-scale galaxy distribution and allow a high value for the Hubble constant. The low order multipoles and quadrupole anisotropy that are potentially observable by COBE and other ongoing experiments should definitively test these models.

  10. The study of PDF turbulence models in combustion

    NASA Technical Reports Server (NTRS)

    Hsu, Andrew T.

    1991-01-01

    The accurate prediction of turbulent combustion is still beyond reach for today's computation techniques. It is the consensus of the combustion profession that the predictions of chemically reacting flow were poor if conventional turbulence models were used. The main difficulty lies in the fact that the reaction rate is highly nonlinear, and the use of averaged temperature, pressure, and density produces excessively large errors. The probability density function (PDF) method is the only alternative at the present time that uses local instant values of the temperature, density, etc. in predicting chemical reaction rate, and thus it is the only viable approach for turbulent combustion calculations.

  11. The Fate of Exoplanetary Systems and the Implications for White Dwarf Pollution

    NASA Astrophysics Data System (ADS)

    Veras, D.; Mustill, A. J.; Bonsor, A.; Wyatt, M. C.

    2013-09-01

    Mounting discoveries of extrasolar planets orbiting post-main-sequence stars motivate studies to understand the fate of these planets. Also, polluted white dwarfs (WDs) likely represent dynamically active systems at late times. Here, we perform full-lifetime simulations of one-, two- and three-planet systems from the endpoint of formation to several Gyr into the WD phase of the host star. We outline the physical and computational processes which must be considered for post-main-sequence planetary studies, and characterize the challenges in explaining the robust observational signatures of infrared excess in white dwarfs by appealing to late-stage planetary systems.

  12. The use of self-organising maps for anomalous behaviour detection in a digital investigation.

    PubMed

    Fei, B K L; Eloff, J H P; Olivier, M S; Venter, H S

    2006-10-16

    The dramatic increase in crime relating to the Internet and computers has caused a growing need for digital forensics. Digital forensic tools have been developed to assist investigators in conducting a proper investigation into digital crimes. In general, the bulk of the digital forensic tools available on the market permit investigators to analyse data that has been gathered from a computer system. However, current state-of-the-art digital forensic tools simply cannot handle large volumes of data in an efficient manner. With the advent of the Internet, many employees have been given access to new and more interesting possibilities via their desktop. Consequently, excessive Internet usage for non-job purposes and even blatant misuse of the Internet have become a problem in many organisations. Since storage media are steadily growing in size, the process of analysing multiple computer systems during a digital investigation can easily consume an enormous amount of time. Identifying a single suspicious computer from a set of candidates can therefore reduce human processing time and monetary costs involved in gathering evidence. The focus of this paper is to demonstrate how, in a digital investigation, digital forensic tools and the self-organising map (SOM)--an unsupervised neural network model--can aid investigators to determine anomalous behaviours (or activities) among employees (or computer systems) in a far more efficient manner. By analysing the different SOMs (one for each computer system), anomalous behaviours are identified and investigators are assisted to conduct the analysis more efficiently. The paper will demonstrate how the easy visualisation of the SOM enhances the ability of the investigators to interpret and explore the data generated by digital forensic tools so as to determine anomalous behaviours.

  13. Pattern of cancer risk in persons with AIDS in Italy in the HAART era

    PubMed Central

    Dal Maso, L; Polesel, J; Serraino, D; Lise, M; Piselli, P; Falcini, F; Russo, A; Intrieri, T; Vercelli, M; Zambon, P; Tagliabue, G; Zanetti, R; Federico, M; Limina, R M; Mangone, L; De Lisi, V; Stracci, F; Ferretti, S; Piffer, S; Budroni, M; Donato, A; Giacomin, A; Bellù, F; Fusco, M; Madeddu, A; Vitarelli, S; Tessandori, R; Tumino, R; Suligoi, B; Franceschi, S

    2009-01-01

    A record-linkage study was carried out between the Italian AIDS Registry and 24 Italian cancer registries to compare cancer excess among persons with HIV/AIDS (PWHA) before and after the introduction of highly active antiretroviral therapy (HAART) in 1996. Standardised incidence ratios (SIR) were computed in 21951 AIDS cases aged 16–69 years reported between 1986 and 2005. Of 101 669 person-years available, 45 026 were after 1996. SIR for Kaposi sarcoma (KS) and non-Hodgkin lymphoma greatly decreased in 1997–2004 compared with 1986–1996, but high SIRs for KS persisted in the increasingly large fraction of PWHA who had an interval of <1 year between first HIV-positive test and AIDS diagnosis. A significant excess of liver cancer (SIR=6.4) emerged in 1997–2004, whereas the SIRs for cancer of the cervix (41.5), anus (44.0), lung (4.1), brain (3.2), skin (non-melanoma, 1.8), Hodgkin lymphoma (20.7), myeloma (3.9), and non-AIDS-defining cancers (2.2) were similarly elevated in the two periods. The excess of some potentially preventable cancers in PWHA suggests that HAART use must be accompanied by cancer-prevention strategies, notably antismoking and cervical cancer screening programmes. Improvements in the timely identification of HIV-positive individuals are also a priority in Italy to avoid the adverse consequences of delayed HAART use. PMID:19223894

  14. The Dark Side of Internet Use: Two Longitudinal Studies of Excessive Internet Use, Depressive Symptoms, School Burnout and Engagement Among Finnish Early and Late Adolescents.

    PubMed

    Salmela-Aro, Katariina; Upadyaya, Katja; Hakkarainen, Kai; Lonka, Kirsti; Alho, Kimmo

    2017-02-01

    Recent research shows an increased concern with well-being at school and potential problems associated with students' use of socio-digital technologies, i.e., the mobile devices, computers, social media, and the Internet. Simultaneously with supporting creative social activities, socio-digital participation may also lead to compulsive and addictive behavioral patterns affecting both general and school-related mental health problems. Using two longitudinal data waves gathered among 1702 (53 % female) early (age 12-14) and 1636 (64 % female) late (age 16-18) Finnish adolescents, we examined cross-lagged paths between excessive internet use, school engagement and burnout, and depressive symptoms. Structural equation modeling revealed reciprocal cross-lagged paths between excessive internet use and school burnout among both adolescent groups: school burnout predicted later excessive internet use and excessive internet use predicted later school burnout. Reciprocal paths between school burnout and depressive symptoms were also found. Girls typically suffered more than boys from depressive symptoms and, in late adolescence, school burnout. Boys, in turn, more typically suffered from excessive internet use. These results show that, among adolescents, excessive internet use can be a cause of school burnout that can later spill over to depressive symptoms.

  15. Optimization of Ozonation Process for the Reduction of Excess Sludge Production from Activated Sludge Process of Sago Industry Wastewater Using Central Composite Design

    PubMed Central

    Subha, B.; Muthukumar, M.

    2012-01-01

    Sago industries effluent containing large amounts of organic content produced excess sludge which is a serious problem in wastewater treatment. In this study ozonation has been employed for the reduction of excess sludge production in activated sludge process. Central composite design is used to study the effect of ozone treatment for the reduction of excess sludge production in sago effluent and to optimise the variables such as pH, ozonation time, and retention time. ANOVA showed that the coefficient determination value (R 2) of VSS and COD reduction were 0.9689 and 0.8838, respectively. VSS reduction (81%) was achieved at acidic pH 6.9, 12 minutes ozonation, and retention time of 10 days. COD reduction (87%) was achieved at acidic pH 6.7, 8 minutes of ozonation time, and retention time of 6 days. Low ozonation time and high retention time influence maximum sludge reduction, whereas low ozonation time with low retention time was effective for COD reduction. PMID:22593666

  16. Predicted cancer risks induced by computed tomography examinations during childhood, by a quantitative risk assessment approach.

    PubMed

    Journy, Neige; Ancelet, Sophie; Rehel, Jean-Luc; Mezzarobba, Myriam; Aubert, Bernard; Laurier, Dominique; Bernier, Marie-Odile

    2014-03-01

    The potential adverse effects associated with exposure to ionizing radiation from computed tomography (CT) in pediatrics must be characterized in relation to their expected clinical benefits. Additional epidemiological data are, however, still awaited for providing a lifelong overview of potential cancer risks. This paper gives predictions of potential lifetime risks of cancer incidence that would be induced by CT examinations during childhood in French routine practices in pediatrics. Organ doses were estimated from standard radiological protocols in 15 hospitals. Excess risks of leukemia, brain/central nervous system, breast and thyroid cancers were predicted from dose-response models estimated in the Japanese atomic bomb survivors' dataset and studies of medical exposures. Uncertainty in predictions was quantified using Monte Carlo simulations. This approach predicts that 100,000 skull/brain scans in 5-year-old children would result in eight (90 % uncertainty interval (UI) 1-55) brain/CNS cancers and four (90 % UI 1-14) cases of leukemia and that 100,000 chest scans would lead to 31 (90 % UI 9-101) thyroid cancers, 55 (90 % UI 20-158) breast cancers, and one (90 % UI <0.1-4) leukemia case (all in excess of risks without exposure). Compared to background risks, radiation-induced risks would be low for individuals throughout life, but relative risks would be highest in the first decades of life. Heterogeneity in the radiological protocols across the hospitals implies that 5-10 % of CT examinations would be related to risks 1.4-3.6 times higher than those for the median doses. Overall excess relative risks in exposed populations would be 1-10 % depending on the site of cancer and the duration of follow-up. The results emphasize the potential risks of cancer specifically from standard CT examinations in pediatrics and underline the necessity of optimization of radiological protocols.

  17. Software for Simulating a Complex Robot

    NASA Technical Reports Server (NTRS)

    Goza, S. Michael

    2003-01-01

    RoboSim (Robot Simulation) is a computer program that simulates the poses and motions of the Robonaut a developmental anthropomorphic robot that has a complex system of joints with 43 degrees of freedom and multiple modes of operation and control. RoboSim performs a full kinematic simulation of all degrees of freedom. It also includes interface components that duplicate the functionality of the real Robonaut interface with control software and human operators. Basically, users see no difference between the real Robonaut and the simulation. Consequently, new control algorithms can be tested by computational simulation, without risk to the Robonaut hardware, and without using excessive Robonaut-hardware experimental time, which is always at a premium. Previously developed software incorporated into RoboSim includes Enigma (for graphical displays), OSCAR (for kinematical computations), and NDDS (for communication between the Robonaut and external software). In addition, RoboSim incorporates unique inverse-kinematical algorithms for chains of joints that have fewer than six degrees of freedom (e.g., finger joints). In comparison with the algorithms of OSCAR, these algorithms are more readily adaptable and provide better results when using equivalent sets of data.

  18. Long-term health experience of jet engine manufacturing workers: IX. further investigation of general mortality patterns in relation to workplace exposures.

    PubMed

    Youk, Ada O; Marsh, Gary M; Buchanich, Jeanine M; Downing, Sarah; Kennedy, Kathleen J; Esmen, Nurtan A; Hancock, Roger P; Lacey, Steven E

    2013-06-01

    To evaluate mortality rates among a cohort of jet engine manufacturing workers. Subjects were 222,123 workers employed from 1952 to 2001. Vital status was determined through 2004 for 99% of subjects and cause of death for 95% of 68,317 deaths. We computed standardized mortality ratios and modeled internal cohort rates. Mortality excesses reported initially no longer met the criteria for further investigation. We found two chronic obstructive pulmonary disease-related mortality excesses that met the criteria in two of eight study plants. At the total cohort level, chronic obstructive pulmonary disease-related categories were not related to any factors or occupational exposures considered. A full evaluation of these excesses was limited by lack of data on smoking history. Occupational exposures received outside of work or uncontrolled positive confounding by smoking cannot be ruled out as reasons for these excesses.

  19. Decreasing excessive media usage while increasing physical activity: a single-subject research study.

    PubMed

    Larwin, Karen H; Larwin, David A

    2008-11-01

    The Kaiser Family Foundation released a report entitled Kids and Media Use in the United States that concluded that children's use of media--including television, computers, Internet, video games, and phones--may be one of the primary contributor's to the poor fitness and obesity of many of today's adolescents. The present study examines the potential of increasing physical activity and decreasing media usage in a 14-year-old adolescent female by making time spent on the Internet and/or cell phone contingent on physical activity. Results of this investigation indicate that requiring the participant to earn her media-usage time did correspond with an increase in physical activity and a decrease in media-usage time relative to baseline measures. Five weeks after cessation of the intervention, the participant's new level of physical activity was still being maintained. One year after the study, the participant's level of physical activity continued to increase.

  20. Coherent dynamics of a telecom-wavelength entangled photon source.

    PubMed

    Ward, M B; Dean, M C; Stevenson, R M; Bennett, A J; Ellis, D J P; Cooper, K; Farrer, I; Nicoll, C A; Ritchie, D A; Shields, A J

    2014-01-01

    Quantum networks can interconnect remote quantum information processors, allowing interaction between different architectures and increasing net computational power. Fibre-optic telecommunications technology offers a practical platform for routing weakly interacting photonic qubits, allowing quantum correlations and entanglement to be established between distant nodes. Although entangled photons have been produced at telecommunications wavelengths using spontaneous parametric downconversion in nonlinear media, as system complexity increases their inherent excess photon generation will become limiting. Here we demonstrate entangled photon pair generation from a semiconductor quantum dot at a telecommunications wavelength. Emitted photons are intrinsically anti-bunched and violate Bell's inequality by 17 standard deviations High-visibility oscillations of the biphoton polarization reveal the time evolution of the emitted state with exceptional clarity, exposing long coherence times. Furthermore, we introduce a method to evaluate the fidelity to a time-evolving Bell state, revealing entanglement between photons emitted up to 5 ns apart, exceeding the exciton lifetime.

  1. Development of a semi-automated model identification and calibration tool for conceptual modelling of sewer systems.

    PubMed

    Wolfs, Vincent; Villazon, Mauricio Florencio; Willems, Patrick

    2013-01-01

    Applications such as real-time control, uncertainty analysis and optimization require an extensive number of model iterations. Full hydrodynamic sewer models are not sufficient for these applications due to the excessive computation time. Simplifications are consequently required. A lumped conceptual modelling approach results in a much faster calculation. The process of identifying and calibrating the conceptual model structure could, however, be time-consuming. Moreover, many conceptual models lack accuracy, or do not account for backwater effects. To overcome these problems, a modelling methodology was developed which is suited for semi-automatic calibration. The methodology is tested for the sewer system of the city of Geel in the Grote Nete river basin in Belgium, using both synthetic design storm events and long time series of rainfall input. A MATLAB/Simulink(®) tool was developed to guide the modeller through the step-wise model construction, reducing significantly the time required for the conceptual modelling process.

  2. 7 CFR 2.93 - Director, Office of Procurement and Property Management.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... agricultural sciences, related to establishing and implementing Federal biobased procurement and voluntary... available to organizations excess or surplus computers or other technical equipment of the Department for...

  3. 7 CFR 2.93 - Director, Office of Procurement and Property Management.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... agricultural sciences, related to establishing and implementing Federal biobased procurement and voluntary... available to organizations excess or surplus computers or other technical equipment of the Department for...

  4. 7 CFR 2.93 - Director, Office of Procurement and Property Management.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... agricultural sciences, related to establishing and implementing Federal biobased procurement and voluntary... available to organizations excess or surplus computers or other technical equipment of the Department for...

  5. 7 CFR 2.93 - Director, Office of Procurement and Property Management.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... agricultural sciences, related to establishing and implementing Federal biobased procurement and voluntary... available to organizations excess or surplus computers or other technical equipment of the Department for...

  6. Television watching, videogames, and excess of body fat in Spanish adolescents: the AVENA study.

    PubMed

    Vicente-Rodríguez, Germán; Rey-López, J Pablo; Martín-Matillas, Miguel; Moreno, Luis A; Wärnberg, Julia; Redondo, Carlos; Tercedor, Pablo; Delgado, Manuel; Marcos, Ascensión; Castillo, Manuel; Bueno, Manuel

    2008-01-01

    We assessed the individual association of sedentary behaviors with the risk of overweight and excess body fat (overfat) in adolescents. A representative sample (1960 subjects, 1012 males, age 13-18.5 y) of Spanish adolescents was studied within the framework of the Alimentación y Valoración del Estado Nutricional de los Adolescentes (AVENA) study. Television (TV) watching, videogame and computer usage, doing homework, and the way students got to school, physical activity, and socioeconomic status were analyzed. Anthropometrics were measured to describe overweight (International Obesity Task Force cutoffs for body mass index) and overfat (body fat percentage >85th percentile). When all subjects were considered as an entire group, the overweight risk increased by 15.8% (P < 0.05) per increasing hour of TV watching. The overweight risks decreased by 32.5% in females, 22% per increasing year of age, and 12.5% by increasing socioeconomic status by 1 U (all Ps < 0.05). The obesity risks decreased with age by 17.8% per year in males and 27.1% in females (both Ps < 0.05). The overfat risks increased by 26.8% and 9.4% per increasing hour of TV and weekend videogame usage, respectively (both Ps < 0.05). In males, the overfat risk increased by 21.5% per increasing hour in weekend videogame usage (P < 0.05). Each hour of TV use increased the overfat risks by 22% in males and 28.3% in females (both Ps < 0.05). Time spent watching TV increased the risk of overweight and obesity in Spanish adolescents, but the effect was influenced by age, sex, and socioeconomic status. Moreover, an excess of body fat was more directly explained by the time spent watching TV and playing videogames during the weekend.

  7. 26 CFR 54.4972-1 - Tax on excess contributions to plans benefiting self-employed individuals.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) and this paragraph for the 1978 taxable year is $15,000, computed as follows: the difference between... paragraph for the 1980 taxable year is $5,000, computed as follows: the difference between (A) $25,000, the...)(4) and this paragraph for 1976 is $10,000 (the difference between (A) $40,000, the amount...

  8. Use of large-scale atmospheric energetics for understanding the dynamics of contrasting Indian summer monsoon rainfall in different years

    NASA Astrophysics Data System (ADS)

    Dutta, Somenath; Narkhedkar, Sanjay G.; Mukhopadhyay, Parthasarathi; Yadav, Mamta; Sunitha Devi

    2018-06-01

    An attempt has been made to understand the dynamics of contrasting Indian summer monsoon rainfall (ISMR) in different years during 1979-2017, from large-scale atmospheric energetics aspects. Daily values of eddy and zonal available potential energy (APE), their generation, eddy and zonal kinetic energy (KE), conversions of zonal KE and eddy APE to eddy KE, and conversions of zonal APE to zonal KE and eddy APE were computed over the region bounded by 65°E-95°E and 5°N-35°N during the period 1 May to 30 September for 39 years (1979-2017), using daily ECMWF reanalyzed atmospheric data at 0.125° × 0.125° resolution (3 components of wind and temperature). ISMR was classified into three categories, viz., deficient and below normal, normal and above normal and excess. The daily anomaly of these energetics parameters in each of these years was computed using jackknife method and then the composite of the daily anomalies of these parameters constructed for the years with the above-mentioned three categories of ISMR. The following salient features emerge from this study: Analysis of composite anomaly shows that in case of excess and above normal (below normal and deficient) ISMR, C(A Z , K Z) was less (more) than normal. In case of excess and above normal (below normal and deficient) ISMR, C(A E , K E) was more (less) than normal. Broadly, C(A Z , A E) was more than normal in the years with deficient and below normal ISMR, whereas it was less than normal for years with excess and above normal ISMR. Broadly, G(A Z) was below normal for the years with above normal and excess ISMR, whereas it was above normal for the years with below normal and deficient ISMR. Total kinetic energy and total conversion to eddy kinetic energy was above normal for the years with above normal and excess ISMR.

  9. Correlates of video games playing among adolescents in an Islamic country

    PubMed Central

    2010-01-01

    Background No study has ever explored the prevalence and correlates of video game playing among children in the Islamic Republic of Iran. This study describes patterns and correlates of excessive video game use in a random sample of middle-school students in Iran. Specifically, we examine the relationship between video game playing and psychological well-being, aggressive behaviors, and adolescents' perceived threat of video-computer game playing. Methods This cross-sectional study was performed with a random sample of 444 adolescents recruited from eight middle schools. A self-administered, anonymous questionnaire covered socio-demographics, video gaming behaviors, mental health status, self-reported aggressive behaviors, and perceived side effects of video game playing. Results Overall, participants spent an average of 6.3 hours per week playing video games. Moreover, 47% of participants reported that they had played one or more intensely violent games. Non-gamers reported suffering poorer mental health compared to excessive gamers. Both non-gamers and excessive gamers overall reported suffering poorer mental health compared to low or moderate players. Participants who initiated gaming at younger ages were more likely to score poorer in mental health measures. Participants' self-reported aggressive behaviors were associated with length of gaming. Boys, but not girls, who reported playing video games excessively showed more aggressive behaviors. A multiple binary logistic regression shows that when controlling for other variables, older students, those who perceived less serious side effects of video gaming, and those who have personal computers, were more likely to report that they had played video games excessively. Conclusion Our data show a curvilinear relationship between video game playing and mental health outcomes, with "moderate" gamers faring best and "excessive" gamers showing mild increases in problematic behaviors. Interestingly, "non-gamers" clearly show the worst outcomes. Therefore, both children and parents of non-game players should be updated about the positive impact of moderate video gaming. Educational interventions should also be designed to educate adolescents and their parents of the possible harmful impact of excessive video game playing on their health and psychosocial functioning. PMID:20507610

  10. Correlates of video games playing among adolescents in an Islamic country.

    PubMed

    Allahverdipour, Hamid; Bazargan, Mohsen; Farhadinasab, Abdollah; Moeini, Babak

    2010-05-27

    No study has ever explored the prevalence and correlates of video game playing among children in the Islamic Republic of Iran. This study describes patterns and correlates of excessive video game use in a random sample of middle-school students in Iran. Specifically, we examine the relationship between video game playing and psychological well-being, aggressive behaviors, and adolescents' perceived threat of video-computer game playing. This cross-sectional study was performed with a random sample of 444 adolescents recruited from eight middle schools. A self-administered, anonymous questionnaire covered socio-demographics, video gaming behaviors, mental health status, self-reported aggressive behaviors, and perceived side effects of video game playing. Overall, participants spent an average of 6.3 hours per week playing video games. Moreover, 47% of participants reported that they had played one or more intensely violent games. Non-gamers reported suffering poorer mental health compared to excessive gamers. Both non-gamers and excessive gamers overall reported suffering poorer mental health compared to low or moderate players. Participants who initiated gaming at younger ages were more likely to score poorer in mental health measures. Participants' self-reported aggressive behaviors were associated with length of gaming. Boys, but not girls, who reported playing video games excessively showed more aggressive behaviors. A multiple binary logistic regression shows that when controlling for other variables, older students, those who perceived less serious side effects of video gaming, and those who have personal computers, were more likely to report that they had played video games excessively. Our data show a curvilinear relationship between video game playing and mental health outcomes, with "moderate" gamers faring best and "excessive" gamers showing mild increases in problematic behaviors. Interestingly, "non-gamers" clearly show the worst outcomes. Therefore, both children and parents of non-game players should be updated about the positive impact of moderate video gaming. Educational interventions should also be designed to educate adolescents and their parents of the possible harmful impact of excessive video game playing on their health and psychosocial functioning.

  11. Map visualization of groundwater withdrawals at the sub-basin scale

    NASA Astrophysics Data System (ADS)

    Goode, Daniel J.

    2016-06-01

    A simple method is proposed to visualize the magnitude of groundwater withdrawals from wells relative to user-defined water-resource metrics. The map is solely an illustration of the withdrawal magnitudes, spatially centered on wells—it is not capture zones or source areas contributing recharge to wells. Common practice is to scale the size (area) of withdrawal well symbols proportional to pumping rate. Symbols are drawn large enough to be visible, but not so large that they overlap excessively. In contrast to such graphics-based symbol sizes, the proposed method uses a depth-rate index (length per time) to visualize the well withdrawal rates by volumetrically consistent areas, called "footprints". The area of each individual well's footprint is the withdrawal rate divided by the depth-rate index. For example, the groundwater recharge rate could be used as a depth-rate index to show how large withdrawals are relative to that recharge. To account for the interference of nearby wells, composite footprints are computed by iterative nearest-neighbor distribution of excess withdrawals on a computational and display grid having uniform square cells. The map shows circular footprints at individual isolated wells and merged footprint areas where wells' individual footprints overlap. Examples are presented for depth-rate indexes corresponding to recharge, to spatially variable stream baseflow (normalized by basin area), and to the average rate of water-table decline (scaled by specific yield). These depth-rate indexes are water-resource metrics, and the footprints visualize the magnitude of withdrawals relative to these metrics.

  12. Map visualization of groundwater withdrawals at the sub-basin scale

    USGS Publications Warehouse

    Goode, Daniel J.

    2016-01-01

    A simple method is proposed to visualize the magnitude of groundwater withdrawals from wells relative to user-defined water-resource metrics. The map is solely an illustration of the withdrawal magnitudes, spatially centered on wells—it is not capture zones or source areas contributing recharge to wells. Common practice is to scale the size (area) of withdrawal well symbols proportional to pumping rate. Symbols are drawn large enough to be visible, but not so large that they overlap excessively. In contrast to such graphics-based symbol sizes, the proposed method uses a depth-rate index (length per time) to visualize the well withdrawal rates by volumetrically consistent areas, called “footprints”. The area of each individual well’s footprint is the withdrawal rate divided by the depth-rate index. For example, the groundwater recharge rate could be used as a depth-rate index to show how large withdrawals are relative to that recharge. To account for the interference of nearby wells, composite footprints are computed by iterative nearest-neighbor distribution of excess withdrawals on a computational and display grid having uniform square cells. The map shows circular footprints at individual isolated wells and merged footprint areas where wells’ individual footprints overlap. Examples are presented for depth-rate indexes corresponding to recharge, to spatially variable stream baseflow (normalized by basin area), and to the average rate of water-table decline (scaled by specific yield). These depth-rate indexes are water-resource metrics, and the footprints visualize the magnitude of withdrawals relative to these metrics.

  13. Study of Using Excess Stock to Reduce Naval Aviation Depot-Level Repairable Piece Part Backorders

    DTIC Science & Technology

    2016-12-01

    Designator Code, may get involved to ensure timely receipt. When a high-priority (Issue Priority Group 1) requisition is backordered, a CAS...alternative source for acquiring bit-piece parts is Navy excess material. Excess material is inventory designated by Navy organizations as meeting...potential alternative source for acquiring bit-piece parts is Navy excess material. Excess material is inventory designated by Navy organizations as

  14. Measurement of Relaxation Time of Excess Carriers in Si and CIGS Solar Cells by Modulated Electroluminescence Technique

    DOE PAGES

    Khatavkar, Sanchit; Muniappan, Kulasekaran; Kannan, Chinna V.; ...

    2017-11-10

    Excess carrier lifetime plays a crucial role in determining the efficiency of solar cells. In this paper, we use the frequency dependence of inphase and quadrature components of modulated electroluminescence (MEL) to measure the relaxation time (decay) of excess carriers. The advantage of the MEL technique is that the relaxation time is obtained directly from the angular frequency at which the quadrature component peaks. It does not need knowledge of the material parameters like mobility, etc., and can be used for any finished solar cells which have detectable light emission. The experiment is easy to perform with standard electrical equipment.more » For silicon solar cells, the relaxation time is dominated by recombination and hence, the relaxation time is indeed the excess carrier lifetime. In contrast, for the CIGS solar cells investigated here, the relaxation time is dominated by trapping and emission from shallow minority carrier traps.« less

  15. Measurement of Relaxation Time of Excess Carriers in Si and CIGS Solar Cells by Modulated Electroluminescence Technique

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khatavkar, Sanchit; Muniappan, Kulasekaran; Kannan, Chinna V.

    Excess carrier lifetime plays a crucial role in determining the efficiency of solar cells. In this paper, we use the frequency dependence of inphase and quadrature components of modulated electroluminescence (MEL) to measure the relaxation time (decay) of excess carriers. The advantage of the MEL technique is that the relaxation time is obtained directly from the angular frequency at which the quadrature component peaks. It does not need knowledge of the material parameters like mobility, etc., and can be used for any finished solar cells which have detectable light emission. The experiment is easy to perform with standard electrical equipment.more » For silicon solar cells, the relaxation time is dominated by recombination and hence, the relaxation time is indeed the excess carrier lifetime. In contrast, for the CIGS solar cells investigated here, the relaxation time is dominated by trapping and emission from shallow minority carrier traps.« less

  16. 31 CFR 360.12 - Disposition of excess.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... STATES SAVINGS BONDS, SERIES I Limitations on Annual Purchases § 360.12 Disposition of excess. If any person at any time has savings bonds issued during any one calendar year in excess of the prescribed...

  17. 31 CFR 360.12 - Disposition of excess.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... STATES SAVINGS BONDS, SERIES I Limitations on Annual Purchases § 360.12 Disposition of excess. If any person at any time has savings bonds issued during any one calendar year in excess of the prescribed...

  18. 31 CFR 353.12 - Disposition of excess.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... STATES SAVINGS BONDS, SERIES EE AND HH Limitations on Annual Purchases § 353.12 Disposition of excess. If any person at any time has savings bonds issued during any one calendar year in excess of the...

  19. 31 CFR 353.12 - Disposition of excess.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... STATES SAVINGS BONDS, SERIES EE AND HH Limitations on Annual Purchases § 353.12 Disposition of excess. If any person at any time has savings bonds issued during any one calendar year in excess of the...

  20. 31 CFR 353.12 - Disposition of excess.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... STATES SAVINGS BONDS, SERIES EE AND HH Limitations on Annual Purchases § 353.12 Disposition of excess. If any person at any time has savings bonds issued during any one calendar year in excess of the...

  1. 31 CFR 360.12 - Disposition of excess.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... STATES SAVINGS BONDS, SERIES I Limitations on Annual Purchases § 360.12 Disposition of excess. If any person at any time has savings bonds issued during any one calendar year in excess of the prescribed...

  2. Regionalization of meso-scale physically based nitrogen modeling outputs to the macro-scale by the use of regression trees

    NASA Astrophysics Data System (ADS)

    Künne, A.; Fink, M.; Kipka, H.; Krause, P.; Flügel, W.-A.

    2012-06-01

    In this paper, a method is presented to estimate excess nitrogen on large scales considering single field processes. The approach was implemented by using the physically based model J2000-S to simulate the nitrogen balance as well as the hydrological dynamics within meso-scale test catchments. The model input data, the parameterization, the results and a detailed system understanding were used to generate the regression tree models with GUIDE (Loh, 2002). For each landscape type in the federal state of Thuringia a regression tree was calibrated and validated using the model data and results of excess nitrogen from the test catchments. Hydrological parameters such as precipitation and evapotranspiration were also used to predict excess nitrogen by the regression tree model. Hence they had to be calculated and regionalized as well for the state of Thuringia. Here the model J2000g was used to simulate the water balance on the macro scale. With the regression trees the excess nitrogen was regionalized for each landscape type of Thuringia. The approach allows calculating the potential nitrogen input into the streams of the drainage area. The results show that the applied methodology was able to transfer the detailed model results of the meso-scale catchments to the entire state of Thuringia by low computing time without losing the detailed knowledge from the nitrogen transport modeling. This was validated with modeling results from Fink (2004) in a catchment lying in the regionalization area. The regionalized and modeled excess nitrogen correspond with 94%. The study was conducted within the framework of a project in collaboration with the Thuringian Environmental Ministry, whose overall aim was to assess the effect of agro-environmental measures regarding load reduction in the water bodies of Thuringia to fulfill the requirements of the European Water Framework Directive (Bäse et al., 2007; Fink, 2006; Fink et al., 2007).

  3. Mesoamerican nephropathy: geographical distribution and time trends of chronic kidney disease mortality between 1970 and 2012 in Costa Rica.

    PubMed

    Wesseling, Catharina; van Wendel de Joode, Berna; Crowe, Jennifer; Rittner, Ralf; Sanati, Negin A; Hogstedt, Christer; Jakobsson, Kristina

    2015-10-01

    Mesoamerican nephropathy is an epidemic of chronic kidney disease (CKD) unrelated to traditional causes, mostly observed in sugarcane workers. We analysed CKD mortality in Costa Rica to explore when and where the epidemic emerged, sex and age patterns, and relationship with altitude, climate and sugarcane production. SMRs for CKD deaths (1970-2012) among population aged ≥20 were computed for 7 provinces and 81 counties over 4 time periods. Time trends were assessed with age-standardised mortality rates. We qualitatively examined relations between mortality and data on altitude, climate and sugarcane production. During 1970-2012, age-adjusted mortality rates in the Guanacaste province increased among men from 4.4 to 38.5 per 100,000 vs. 3.6-8.4 in the rest of Costa Rica, and among women from 2.3 to 10.7 per 100,000 vs. 2.6-5.0 in the rest of Costa Rica. A significant moderate excess mortality was observed among men in Guanacaste already in the mid-1970s, steeply increasing thereafter; a similar female excess mortality appeared a decade later, remaining stable. Male age-specific rates were high in Guanacaste for age categories ≥30, and since the late 1990s also for age range 20-29. The male spatiotemporal patterns roughly followed sugarcane expansion in hot, dry lowlands with manual harvesting. Excess CKD mortality occurs primarily in Guanacaste lowlands and was already present 4 decades ago. The increasing rates among Guanacaste men in hot, dry lowland counties with sugarcane are consistent with an occupational component. Stable moderate increases among women, and among men in counties without sugarcane, suggest coexisting environmental risk factors. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  4. Dielectric relaxation studies of binary mixture of β-picoline and methanol using time domain reflectometry at different temperatures

    NASA Astrophysics Data System (ADS)

    Trivedi, C. M.; Rana, V. A.; Hudge, P. G.; Kumbharkhane, A. C.

    2016-08-01

    Complex permittivity spectra of binary mixtures of varying concentrations of β-picoline and Methanol (MeOH) have been obtained using time domain reflectometry (TDR) technique over frequency range 10 MHz to 25 GHz at 283.15, 288.15, 293.15 and 298.15 K temperatures. The dielectric relaxation parameters namely static permittivity (ɛ0), high frequency limit permittivity (ɛ∞1) and the relaxation time (τ) were determined by fitting complex permittivity data to the single Debye/Cole-Davidson model. Complex nonlinear least square (CNLS) fitting procedure was carried out using LEVMW software. The excess permittivity (ɛ0E) and the excess inverse relaxation time (1/τ)E which contain information regarding molecular structure and interaction between polar-polar liquids were also determined. From the experimental data, parameters such as effective Kirkwood correlation factor (geff), Bruggeman factor (fB) and some thermo dynamical parameters have been calculated. Excess parameters were fitted to the Redlich-Kister polynomial equation. The values of static permittivity and relaxation time increase nonlinearly with increase in the mol-fraction of MeOH at all temperatures. The values of excess static permittivity (ɛ0E) and the excess inverse relaxation time (1/τ)E are negative for the studied β-picoline — MeOH system at all temperatures.

  5. Theoretical study of the composition pulling effect in InGaN metalorganic vapor-phase epitaxy growth

    NASA Astrophysics Data System (ADS)

    Inatomi, Yuya; Kangawa, Yoshihiro; Ito, Tomonori; Suski, Tadeusz; Kumagai, Yoshinao; Kakimoto, Koichi; Koukitu, Akinori

    2017-07-01

    The composition pulling effect in metalorganic vapor-phase InGaN epitaxy was theoretically investigated by thermodynamic analysis. The excess energies of biaxial-strained In x Ga1- x N were numerically calculated using empirical interatomic potentials considering different situations: (i) coherent growth on GaN(0001), (ii) coherent growth on In0.2Ga0.8N(0001), and (iii) bulk growth. Using the excess energies, the excess chemical potentials of InN and GaN alloys were computed. Our results show that compressive strain suppresses In incorporation, whereas tensile strain promotes it. Moreover, assuming chemical equilibrium, the relationship between the solid composition and the growth conditions was predicted. The results successfully reproduced the typical composition pulling effect.

  6. Effect of Surface Excess Energy Transport on the Rupture of an Evaporating Film

    NASA Astrophysics Data System (ADS)

    Luo, Yan; Zhou, Jianqiu; Yang, Xia; Liu, Rong

    2018-05-01

    In most of existing works on the instabilities of an evaporating film, the energy boundary condition only takes into account contributions of the evaporation latent heat and the heat conduction in the liquid. We use a new generalized energy boundary condition at the evaporating liquid-vapor interface, in which the contribution of the transport of the Gibbs excess energy is included. We have derived the long-wave equations in which the thickness of film and the interfacial temperature are coupled to describe the dynamics of an evaporating thin film. The results of our computation show that the transport of the Gibbs excess internal energy delay the rupture of thin films due to van de Waals force, evaporating effect and vapor recoil.

  7. Research and Development on the Storage Ring Vacuum System for the APS Upgrade Project

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stillwell, B.; Brajuskovic, B.; Carter, J.

    A number of research and development activities are underway at Argonne National Laboratory to build confidence in the designs for the storage ring vacuum system required for the Advanced Photon Source Up-grade project (APS-U) [1]. The predominant technical risks are: excessive residual gas pressures during operation; insufficient beam position monitor stability; excessive beam impedance; excessive heating by induced electrical surface currents; and insufficient operational reliability. Present efforts to mitigate these risks include: building and evaluating mockup assemblies; performing mechanical testing of chamber weld joints; developing computational tools; investigating design alternatives; and performing electrical bench measurements. Status of these activities andmore » some of what has been learned to date will be shared.« less

  8. Temperature of maximum density and excess thermodynamics of aqueous mixtures of methanol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    González-Salgado, D.; Zemánková, K.; Noya, E. G.

    In this work, we present a study of representative excess thermodynamic properties of aqueous mixtures of methanol over the complete concentration range, based on extensive computer simulation calculations. In addition to test various existing united atom model potentials, we have developed a new force-field which accurately reproduces the excess thermodynamics of this system. Moreover, we have paid particular attention to the behavior of the temperature of maximum density (TMD) in dilute methanol mixtures. The presence of a temperature of maximum density is one of the essential anomalies exhibited by water. This anomalous behavior is modified in a non-monotonous fashion bymore » the presence of fully miscible solutes that partly disrupt the hydrogen bond network of water, such as methanol (and other short chain alcohols). In order to obtain a better insight into the phenomenology of the changes in the TMD of water induced by small amounts of methanol, we have performed a new series of experimental measurements and computer simulations using various force fields. We observe that none of the force-fields tested capture the non-monotonous concentration dependence of the TMD for highly diluted methanol solutions.« less

  9. 41 CFR 102-75.240 - May excess real property be temporarily assigned/reassigned?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROPERTY 75-REAL PROPERTY DISPOSAL Utilization of Excess Real Property Temporary Utilization § 102-75.240... reported excess at an agreed upon time (see § 102-75.85). The requesting agency is responsible for...

  10. Algorithm-Based Fault Tolerance Integrated with Replication

    NASA Technical Reports Server (NTRS)

    Some, Raphael; Rennels, David

    2008-01-01

    In a proposed approach to programming and utilization of commercial off-the-shelf computing equipment, a combination of algorithm-based fault tolerance (ABFT) and replication would be utilized to obtain high degrees of fault tolerance without incurring excessive costs. The basic idea of the proposed approach is to integrate ABFT with replication such that the algorithmic portions of computations would be protected by ABFT, and the logical portions by replication. ABFT is an extremely efficient, inexpensive, high-coverage technique for detecting and mitigating faults in computer systems used for algorithmic computations, but does not protect against errors in logical operations surrounding algorithms.

  11. Computer use and addiction in Romanian children and teenagers--an observational study.

    PubMed

    Chiriţă, V; Chiriţă, Roxana; Stefănescu, C; Chele, Gabriela; Ilinca, M

    2006-01-01

    The computer has provided some wonderful opportunities for our children. Although research on the effects of children's use of computer is still ambiguous, some initial indications of positive and negative effects are beginning t emerge. They commonly use computers for playing games, completing school assignments, email, and connecting to the Internet. This may sometimes come at the expense of other activities such as homework or normal social interchange. Although most children seem to naturally correct the problem, parents and educators must monitor the signs of misuse. Studies of general computer users suggest that some children's may experience psychological problems such as social isolation, depression, loneliness, and time mismanagement related to their computer use and failure at school. The purpose of this study is to investigate issues related to computer use by school students from 11 to 18 years old. The survey included a representative sample of 439 school students of ages 11 to 18. All of the students came from 3 gymnasium schools and 5 high schools of Iaşi, Romania. The students answered to a questionnaire comprising 34 questions related to computer activities. The children's parents answered to a second questionnaire with the same subject. Most questions supposed to rate on a scale the frequency of occurrence of a certain event or issue; some questions solicited an open-answer or to choose an answer from a list. These were aimed at highlighting: (1) The frequency of computer use by the students; (2) The interference of excessive use with school performance and social life; (3) The identification of a possible computer addiction. The data was processed using the SPSS statistics software, version 11.0. Results show that the school students prefer to spend a considerable amount of time with their computers, over 3 hours/day. More than 65.7% of the students have a computer at home. More than 70% of the parents admit they do not or only occasionally discuss computer use with their children. This indicates the fact that, although they bought a computer for their children, they do not supervise the way it is used. The family is rather a passive presence, vaguely responsible and lacking involvement. But, the parents consider that, for better school results, their children should use their computers. This study tried to identify aspects of computer addiction in gymnasium and high school students, as well.

  12. Evaluation of plasma lactate concentration and base excess at the time of hospital admission as predictors of gastric necrosis and outcome and correlation between those variables in dogs with gastric dilatation-volvulus: 78 cases (2004-2009).

    PubMed

    Beer, Kari A Santoro; Syring, Rebecca S; Drobatz, Kenneth J

    2013-01-01

    To determine the correlation between plasma lactate concentration and base excess at the time of hospital admission and evaluate each variable as a predictor of gastric necrosis or outcome in dogs with gastric dilatation-volvulus (GDV). Retrospective case series. 78 dogs. For each dog, various data, including plasma lactate concentration and base excess at the time of hospital admission, surgical or necropsy findings, and outcome, were collected from medical records. Gastric necrosis was identified in 12 dogs at the time of surgery and in 4 dogs at necropsy. Sixty-five (83%) dogs survived to hospital discharge, whereas 13 (17%) dogs died or were euthanized. Of the 65 survivors and 8 nonsurvivors that underwent surgery, gastric necrosis was detected in 8 and 4 dogs, respectively. Via receiver operating characteristic curve analysis, an initial plasma lactate concentration cutoff of 7.4 mmol/L was 82% accurate for predicting gastric necrosis (sensitivity, 50%; specificity, 88%) and 88% accurate for predicting outcome (sensitivity, 75%; specificity, 89%). Among all dogs, the correlation between initial plasma lactate concentration and base excess was significant, although base excess was a poor discriminator for predicting gastric necrosis or outcome (area under the receiver operating characteristic curve, 0.571 and 0.565, respectively). In dogs with GDV, plasma lactate concentration at the time of hospital admission was a good predictor of gastric necrosis and outcome. However, despite the correlation between initial base excess and plasma lactate concentration, base excess should not be used for prediction of gastric necrosis or outcome in those patients.

  13. FINITE ELEMENT MODEL FOR TIDES AND CURRENTS WITH FIELD APPLICATIONS.

    USGS Publications Warehouse

    Walters, Roy A.

    1988-01-01

    A finite element model, based upon the shallow water equations, is used to calculate tidal amplitudes and currents for two field-scale test problems. Because tides are characterized by line spectra, the governing equations are subjected to harmonic decomposition. Thus the solution variables are the real and imaginary parts of the amplitude of sea level and velocity rather than a time series of these variables. The time series is recovered through synthesis. This scheme, coupled with a modified form of the governing equations, leads to high computational efficiency and freedom from excessive numerical noise. Two test-cases are presented. The first is a solution for eleven tidal constituents in the English Channel and southern North Sea, and three constituents are discussed. The second is an analysis of the frequency response and tidal harmonics for south San Francisco Bay.

  14. Higher-order cumulants and spectral kurtosis for early detection of subterranean termites

    NASA Astrophysics Data System (ADS)

    de la Rosa, Juan José González; Moreno Muñoz, Antonio

    2008-02-01

    This paper deals with termite detection in non-favorable SNR scenarios via signal processing using higher-order statistics. The results could be extrapolated to all impulse-like insect emissions; the situation involves non-destructive termite detection. Fourth-order cumulants in time and frequency domains enhance the detection and complete the characterization of termite emissions, non-Gaussian in essence. Sliding higher-order cumulants offer distinctive time instances, as a complement to the sliding variance, which only reveal power excesses in the signal; even for low-amplitude impulses. The spectral kurtosis reveals non-Gaussian characteristics (the peakedness of the probability density function) associated to these non-stationary measurements, specially in the near ultrasound frequency band. Contrasted estimators have been used to compute the higher-order statistics. The inedited findings are shown via graphical examples.

  15. Universality of market superstatistics

    NASA Astrophysics Data System (ADS)

    Denys, Mateusz; Gubiec, Tomasz; Kutner, Ryszard; Jagielski, Maciej; Stanley, H. Eugene

    2016-10-01

    We use a key concept of the continuous-time random walk formalism, i.e., continuous and fluctuating interevent times in which mutual dependence is taken into account, to model market fluctuation data when traders experience excessive (or superthreshold) losses or excessive (or superthreshold) profits. We analytically derive a class of "superstatistics" that accurately model empirical market activity data supplied by Bogachev, Ludescher, Tsallis, and Bunde that exhibit transition thresholds. We measure the interevent times between excessive losses and excessive profits and use the mean interevent discrete (or step) time as a control variable to derive a universal description of empirical data collapse. Our dominant superstatistic value is a power-law corrected by the lower incomplete gamma function, which asymptotically tends toward robustness but initially gives an exponential. We find that the scaling shape exponent that drives our superstatistics subordinates itself and a "superscaling" configuration emerges. Thanks to the Weibull copula function, our approach reproduces the empirically proven dependence between successive interevent times. We also use the approach to calculate a dynamic risk function and hence the dynamic VaR, which is significant in financial risk analysis. Our results indicate that there is a functional (but not literal) balance between excessive profits and excessive losses that can be described using the same body of superstatistics but different calibration values and driving parameters. We also extend our original approach to cover empirical seismic activity data (e.g., given by Corral), the interevent times of which range from minutes to years. Superpositioned superstatistics is another class of superstatistics that protects power-law behavior both for short- and long-time behaviors. These behaviors describe well the collapse of seismic activity data and capture so-called volatility clustering phenomena.

  16. Planck 2013 results. X. HFI energetic particle effects: characterization, removal, and simulation

    NASA Astrophysics Data System (ADS)

    Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Armitage-Caplan, C.; Arnaud, M.; Ashdown, M.; Atrio-Barandela, F.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bobin, J.; Bock, J. J.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Bridges, M.; Bucher, M.; Burigana, C.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chiang, H. C.; Chiang, L.-Y.; Christensen, P. R.; Church, S.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Delouis, J.-M.; Désert, F.-X.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Dupac, X.; Efstathiou, G.; Enßlin, T. A.; Eriksen, H. K.; Finelli, F.; Forni, O.; Frailis, M.; Franceschi, E.; Galeotta, S.; Ganga, K.; Giard, M.; Girard, D.; Giraud-Héraud, Y.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Hansen, F. K.; Hanson, D.; Harrison, D.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W.; Huffenberger, K. M.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Juvela, M.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Knox, L.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lamarre, J.-M.; Lasenby, A.; Laureijs, R. J.; Lawrence, C. R.; Leonardi, R.; Leroy, C.; Lesgourgues, J.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Mandolesi, N.; Maris, M.; Marshall, D. J.; Martin, P. G.; Martínez-González, E.; Masi, S.; Massardi, M.; Matarrese, S.; Matthai, F.; Mazzotta, P.; McGehee, P.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Miniussi, A.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Mottet, S.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Osborne, S.; Oxborrow, C. A.; Paci, F.; Pagano, L.; Pajot, F.; Paoletti, D.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Poutanen, T.; Pratt, G. W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Racine, B.; Reinecke, M.; Remazeilles, M.; Renault, C.; Ricciardi, S.; Riller, T.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Roudier, G.; Rusholme, B.; Sanselme, L.; Santos, D.; Sauvé, A.; Savini, G.; Scott, D.; Shellard, E. P. S.; Spencer, L. D.; Starck, J.-L.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sureau, F.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Tavagnacco, D.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Umana, G.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Vittorio, N.; Wade, L. A.; Wandelt, B. D.; Yvon, D.; Zacchei, A.; Zonca, A.

    2014-11-01

    We describe the detection, interpretation, and removal of the signal resulting from interactions of high energy particles with the Planck High Frequency Instrument (HFI). There are two types of interactions: heating of the 0.1 K bolometer plate; and glitches in each detector time stream. The transientresponses to detector glitch shapes are not simple single-pole exponential decays and fall into three families. The glitch shape for each family has been characterized empirically in flight data and these shapes have been used to remove glitches from the detector time streams. The spectrum of the count rate per unit energy is computed for each family and a correspondence is made to the location on the detector of the particle hit. Most of the detected glitches are from Galactic protons incident on the die frame supporting the micro-machined bolometric detectors. In the Planck orbit at L2, the particle flux is around 5 cm-2 s-1 and is dominated by protons incident on the spacecraft with energy >39 MeV, at a rate of typically one event per second per detector. Different categories of glitches have different signatures in the time stream. Two of the glitch types have a low amplitude component that decays over nearly 1 s. This component produces excess noise if not properly removed from the time-ordered data. We have used a glitch detection and subtraction method based on the joint fit of population templates. The application of this novel glitch subtraction method removes excess noise from the time streams. Using realistic simulations, we find that this method does not introduce signal bias into the Planck data.

  17. Prevalence of musculoskeletal pain in adolescents and association with computer and videogame use.

    PubMed

    Silva, Georgia Rodrigues Reis; Pitangui, Ana Carolina Rodarti; Xavier, Michele Katherine Andrade; Correia-Júnior, Marco Aurélio Valois; De Araújo, Rodrigo Cappato

    2016-01-01

    This study investigated the presence of musculoskeletal symptoms in high school adolescents from public schools and its association with electronic device use. The sample consisted of 961 boys and girls aged 14-19 years who answered a questionnaire regarding the use of computers and electronic games, and questions about pain symptoms and physical activity. Furthermore, anthropometric assessments of all volunteers were performed. The chi-squared test and a multiple logistic regression model were used for the inferential analysis. The presence of musculoskeletal pain symptoms was reported by 65.1% of the adolescents, being more prevalent in the thoracolumbar spine (46.9%), followed by pain in the upper limbs, representing 20% of complaints. The mean time of use for computers and electronic games was 1.720 and 583 minutes per week, respectively. The excessive use of electronic devices was demonstrated to be a risk factor for cervical and lumbar pain. Female gender was associated with the presence of pain in different body parts. Presence of a paid job was associated with cervical pain. A high prevalence of musculoskeletal pain in adolescents, as well as an increased amount of time using digital devices was observed. However, it was only possible to observe an association between the increased use of these devices and the presence of cervical and low back pain. Copyright © 2015 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  18. Development of the HIDEC inlet integration mode. [Highly Integrated Digital Electronic Control

    NASA Technical Reports Server (NTRS)

    Chisholm, J. D.; Nobbs, S. G.; Stewart, J. F.

    1990-01-01

    The Highly Integrated Digital Electronic Control (HIDEC) development program conducted at NASA-Ames/Dryden will use an F-15 test aircraft for flight demonstration. An account is presently given of the HIDEC Inlet Integration mode's design concept, control law, and test aircraft implementation, with a view to its performance benefits. The enhancement of performance is a function of the use of Digital Electronic Engine Control corrected engine airflow computations to improve the scheduling of inlet ramp positions in real time; excess thrust can thereby be increased by 13 percent at Mach 2.3 and 40,000 ft. Aircraft supportability is also improved through the obviation of inlet controllers.

  19. Development report: Automatic System Test and Calibration (ASTAC) equipment

    NASA Technical Reports Server (NTRS)

    Thoren, R. J.

    1981-01-01

    A microcomputer based automatic test system was developed for the daily performance monitoring of wind energy system time domain (WEST) analyzer. The test system consists of a microprocessor based controller and hybrid interface unit which are used for inputing prescribed test signals into all WEST subsystems and for monitoring WEST responses to these signals. Performance is compared to theoretically correct performance levels calculated off line on a large general purpose digital computer. Results are displayed on a cathode ray tube or are available from a line printer. Excessive drift and/or lack of repeatability of the high speed analog sections within WEST is easily detected and the malfunctioning hardware identified using this system.

  20. Spin rate distribution of small asteroids

    NASA Astrophysics Data System (ADS)

    Pravec, P.; Harris, A. W.; Vokrouhlický, D.; Warner, B. D.; Kušnirák, P.; Hornoch, K.; Pray, D. P.; Higgins, D.; Oey, J.; Galád, A.; Gajdoš, Š.; Kornoš, L.; Világi, J.; Husárik, M.; Krugly, Yu. N.; Shevchenko, V.; Chiorny, V.; Gaftonyuk, N.; Cooney, W. R.; Gross, J.; Terrell, D.; Stephens, R. D.; Dyvig, R.; Reddy, V.; Ries, J. G.; Colas, F.; Lecacheux, J.; Durkee, R.; Masi, G.; Koff, R. A.; Goncalves, R.

    2008-10-01

    The spin rate distribution of main belt/Mars crossing (MB/MC) asteroids with diameters 3-15 km is uniform in the range from f=1 to 9.5 d -1, and there is an excess of slow rotators with f<1 d -1. The observed distribution appears to be controlled by the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect. The magnitude of the excess of slow rotators is related to the residence time of slowed down asteroids in the excess and the rate of spin rate change outside the excess. We estimated a median YORP spin rate change of ≈0.022 d/Myr for asteroids in our sample (i.e., a median time in which the spin rate changes by 1 d -1 is ≈45 Myr), thus the residence time of slowed down asteroids in the excess is ≈110 Myr. The spin rate distribution of near-Earth asteroids (NEAs) with sizes in the range 0.2-3 km (˜5 times smaller in median diameter than the MB/MC asteroids sample) shows a similar excess of slow rotators, but there is also a concentration of NEAs at fast spin rates with f=9-10 d. The concentration at fast spin rates is correlated with a narrower distribution of spin rates of primaries of binary systems among NEAs; the difference may be due to the apparently more evolved population of binaries among MB/MC asteroids.

  1. Slat Cove Unsteadiness Effect of 3D Flow Structures

    NASA Technical Reports Server (NTRS)

    Choudhari, Meelan M.; Khorrami, Mehdi R.

    2006-01-01

    Previous studies have indicated that 2D, time accurate computations based on a pseudo-laminar zonal model of the slat cove region (within the framework of the Reynolds-Averaged Navier-Stokes equations) are inadequate for predicting the full unsteady dynamics of the slat cove flow field. Even though such computations could capture the large-scale, unsteady vorticity structures in the slat cove region without requiring any external forcing, the simulated vortices were excessively strong and the recirculation zone was unduly energetic in comparison with the PIV measurements for a generic high-lift configuration. To resolve this discrepancy and to help enable physics based predictions of slat aeroacoustics, the present paper is focused on 3D simulations of the slat cove flow over a computational domain of limited spanwise extent. Maintaining the pseudo-laminar approach, current results indicate that accounting for the three-dimensionality of flow fluctuations leads to considerable improvement in the accuracy of the unsteady, nearfield solution. Analysis of simulation data points to the likely significance of turbulent fluctuations near the reattachment region toward the generation of broadband slat noise. The computed acoustic characteristics (in terms of the frequency spectrum and spatial distribution) within short distances from the slat resemble the previously reported, subscale measurements of slat noise.

  2. Excessive bleeding predictors after cardiac surgery in adults: integrative review.

    PubMed

    Lopes, Camila Takao; Dos Santos, Talita Raquel; Brunori, Evelise Helena Fadini Reis; Moorhead, Sue A; Lopes, Juliana de Lima; Barros, Alba Lucia Bottura Leite de

    2015-11-01

    To integrate literature data on the predictors of excessive bleeding after cardiac surgery in adults. Perioperative nursing care requires awareness of the risk factors for excessive bleeding after cardiac surgery to assure vigilance prioritising and early correction of those that are modifiable. Integrative literature review. Articles were searched in seven databases. Seventeen studies investigating predictive factors for excessive bleeding after open-heart surgery from 2004-2014 were included. Predictors of excessive bleeding after cardiac surgery were: Patient-related: male gender, higher preoperative haemoglobin levels, lower body mass index, diabetes mellitus, impaired left ventricular function, lower amount of prebypass thrombin generation, lower preoperative platelet counts, decreased preoperative platelet aggregation, preoperative platelet inhibition level >20%, preoperative thrombocytopenia and lower preoperative fibrinogen concentration. Procedure-related: the operating surgeon, coronary artery bypass surgery with three or more bypasses, use of the internal mammary artery, duration of surgery, increased cross-clamp time, increased cardiopulmonary bypass time, lower intraoperative core body temperature and bypass-induced haemostatic disorders. Postoperative: fibrinogen levels and metabolic acidosis. Patient-related, procedure-related and postoperative predictors of excessive bleeding after cardiac surgery were identified. The predictors summarised in this review can be used for risk stratification of excessive bleeding after cardiac surgery. Assessment, documentation and case reporting can be guided by awareness of these factors, so that postoperative vigilance can be prioritised. Timely identification and correction of the modifiable factors can be facilitated. © 2015 John Wiley & Sons Ltd.

  3. Demographic factors and playing variables in online computer gaming.

    PubMed

    Griffiths, Mark D; Davies, Mark N O; Chappell, Darren

    2004-08-01

    Despite the growing popularity of online game playing, there has been no primary survey of its players. Therefore, an online questionnaire survey was used to examine basic demographic factors of online computer game players who played the popular online game Everquest (i.e., gender, age, marital status, nationality, education level, occupation). The survey also examined playing frequency (i.e., amount of time spent playing the game a week), playing history (i.e., how long they had been playing the game, who they played the game with, whether they had ever gender swapped their game character), the favorite and least favorite aspects of playing the game, and what they sacrifice (if anything) to play the game. Results showed that 81% of online game players were male, and that the mean age of players was 27.9 years of age. For many players, the social aspects of the game were the most important factor in playing. A small minority of players appear to play excessively (over 80 h a week), and results suggest that a small minority sacrifice important activities in order to play (e.g., sleep, time with family and/or partner, work, or schooling).

  4. Design by Prototype: Examples from the National Aeronautics and Space Administration

    NASA Technical Reports Server (NTRS)

    Mulenburg, Gerald M.; Gundo, Daniel P.

    2002-01-01

    This paper describes and provides exa.mples of a technique called Design-by-Prototype used in the development of research hardware at the National Aeronautics and Space Administration's (NASA) Ames Research Center. This is not a new idea. Artisans and great masters have used prototyping as a design technique for centuries. They created prototypes to try out their ideas before making the primary artifact they were planning. This abstract is itself a prototype for others to use in determining the value of the paper it describes. At the Ames Research Center Design-by-Prototype is used for developing unique, one-of-a-kind hardware for small, high-risk projects. The need tor this new/old process is the proliferation of computer "design tools" that can result in both excessive time expended in design, and a lack of imbedded reality in the final product. Despite creating beautiful three-dimensional models and detailed computer drawings that can consume hundreds of engineering hours, the resulting designs can be extremely difficult to make, requiring many changes that add to the cost and schedule. Much design time can be saved and expensive rework eliminated using Design-by-Prototype.

  5. Calibration of Complex Subsurface Reaction Models Using a Surrogate-Model Approach

    EPA Science Inventory

    Application of model assessment techniques to complex subsurface reaction models involves numerous difficulties, including non-trivial model selection, parameter non-uniqueness, and excessive computational burden. To overcome these difficulties, this study introduces SAMM (Simult...

  6. Computer analysis of the negative differential resistance switching phenomenon of double-injection devices

    NASA Technical Reports Server (NTRS)

    Shieh, Tsay-Jiu

    1989-01-01

    By directly solving the semiconductor differential equations for the double-injection (DI) devices involving two interacting deep levels, the authors studied the negative differential resistance switching characteristic and its relationship with the device dimension, doping level, and dependence on the deep impurity profile. Computer simulation showed that although one can increase the threshold voltage by increasing the device length, the excessive holding voltage that would follow would put this device in a very limited application such as pulse power source. The excessive leakage current in the low conductance state also jeopardizes the attempt to use the device for any practical purpose. Unless there are new materials and deep impurities found that have a great differential hole and electron capture cross sections and a reasonable energy bandgap for low intrinsic carrier concentration, no big improvement in the fate of DI devices is expected in the near future.

  7. Parameter sensitivity analysis of the mixed Green-Ampt/Curve-Number method for rainfall excess estimation in small ungauged catchments

    NASA Astrophysics Data System (ADS)

    Romano, N.; Petroselli, A.; Grimaldi, S.

    2012-04-01

    With the aim of combining the practical advantages of the Soil Conservation Service - Curve Number (SCS-CN) method and Green-Ampt (GA) infiltration model, we have developed a mixed procedure, which is referred to as CN4GA (Curve Number for Green-Ampt). The basic concept is that, for a given storm, the computed SCS-CN total net rainfall amount is used to calibrate the soil hydraulic conductivity parameter of the Green-Ampt model so as to distribute in time the information provided by the SCS-CN method. In a previous contribution, the proposed mixed procedure was evaluated on 100 observed events showing encouraging results. In this study, a sensitivity analysis is carried out to further explore the feasibility of applying the CN4GA tool in small ungauged catchments. The proposed mixed procedure constrains the GA model with boundary and initial conditions so that the GA soil hydraulic parameters are expected to be insensitive toward the net hyetograph peak. To verify and evaluate this behaviour, synthetic design hyetograph and synthetic rainfall time series are selected and used in a Monte Carlo analysis. The results are encouraging and confirm that the parameter variability makes the proposed method an appropriate tool for hydrologic predictions in ungauged catchments. Keywords: SCS-CN method, Green-Ampt method, rainfall excess, ungauged basins, design hydrograph, rainfall-runoff modelling.

  8. Computationally Aided Absolute Stereochemical Determination of Enantioenriched Amines.

    PubMed

    Zhang, Jun; Gholami, Hadi; Ding, Xinliang; Chun, Minji; Vasileiou, Chrysoula; Nehira, Tatsuo; Borhan, Babak

    2017-03-17

    A simple and efficient protocol for sensing the absolute stereochemistry and enantiomeric excess of chiral monoamines is reported. Preparation of the sample requires a single-step reaction of the 1,1'-(bromomethylene)dinaphthalene (BDN) with the chiral amine. Analysis of the exciton coupled circular dichroism generated from the BDN-derivatized chiral amine sample, along with comparison to conformational analysis performed computationally, yields the absolute stereochemistry of the parent chiral monoamine.

  9. Development and validation of a computational model to study the effect of foot constraint on ankle injury due to external rotation.

    PubMed

    Wei, Feng; Hunley, Stanley C; Powell, John W; Haut, Roger C

    2011-02-01

    Recent studies, using two different manners of foot constraint, potted and taped, document altered failure characteristics in the human cadaver ankle under controlled external rotation of the foot. The posterior talofibular ligament (PTaFL) was commonly injured when the foot was constrained in potting material, while the frequency of deltoid ligament injury was higher for the taped foot. In this study an existing multibody computational modeling approach was validated to include the influence of foot constraint, determine the kinematics of the joint under external foot rotation, and consequently obtain strains in various ligaments. It was hypothesized that the location of ankle injury due to excessive levels of external foot rotation is a function of foot constraint. The results from this model simulation supported this hypothesis and helped to explain the mechanisms of injury in the cadaver experiments. An excessive external foot rotation might generate a PTaFL injury for a rigid foot constraint, and an anterior deltoid ligament injury for a pliant foot constraint. The computational models may be further developed and modified to simulate the human response for different shoe designs, as well as on various athletic shoe-surface interfaces, so as to provide a computational basis for optimizing athletic performance with minimal injury risk.

  10. Cartilage degeneration and excessive subchondral bone formation in spontaneous osteoarthritis involves altered TGF-β signaling.

    PubMed

    Zhao, Weiwei; Wang, Ting; Luo, Qiang; Chen, Yan; Leung, Victor Y L; Wen, Chunyi; Shah, Mohammed F; Pan, Haobo; Chiu, KwongYuen; Cao, Xu; Lu, William W

    2016-05-01

    Transforming growth factor-β (TGF-β) has been demonstrated as a potential therapeutic target in osteoarthritis. However, beneficial effects of TGF-β supplement and inhibition have both been reported, suggesting characterization of the spatiotemporal distribution of TGF-β during the whole time course of osteoarthritis is important. To investigate the activity of TGF-β in osteoarthritis progression, we collected knee joints from Dunkin-Hartley (DH) guinea pigs at 3, 6, 9, and 12-month old (n = 8), which develop spontaneous osteoarthritis in a manner extraordinarily similar to humans. Via histology and micro-computed tomography (CT) analysis, we found that the joints exhibited gradual cartilage degeneration, subchondral plate sclerosis, and elevated bone remodeling during aging. The degenerating cartilage showed a progressive switch of the expression of phosphorylated Smad2/3 to Smad1/5/8, suggesting dual roles of TGF-β/Smad signaling during chondrocyte terminal differentiation in osteoarthritis progression. In subchondral bone, we found that the locations and age-related changes of osterix(+) osteoprogenitors were in parallel with active TGF-β, which implied the excessive osteogenesis may link to the activity of TGF-β. Our study, therefore, suggests an association of cartilage degeneration and excessive bone remodeling with altered TGF-β signaling in osteoarthritis progression of DH guinea pigs. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:763-770, 2016. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  11. A Review: Radiographic Iodinated Contrast Media-Induced Thyroid Dysfunction

    PubMed Central

    Leung, Angela M.; Braverman, Lewis E.; Brent, Gregory A.; Pearce, Elizabeth N.

    2015-01-01

    Context: Thyroid hormone production is dependent on adequate iodine intake. Excess iodine is generally well-tolerated, but thyroid dysfunction can occur in susceptible individuals after excess iodine exposure. Radiological iodinated contrast media represent an increasingly common source of excess iodine. Objective: This review will discuss the thyroidal response after acute exposure to excess iodine; contrast iodine-induced thyroid dysfunction; risks of iodine-induced thyroid dysfunction in vulnerable populations, such as the fetus, neonate, and patients with impaired renal function; and recommendations for the assessment and treatment of contrast iodine-induced thyroid dysfunction. Methods: Data for this review were identified by searching PubMed, Google Scholar, and references from relevant articles from 1948 to 2014. Conclusions: With the increase in the use of computed tomography scans in the United States, there is increasing risk of contrast-induced thyroid dysfunction. Patients at risk of developing iodine-induced thyroid dysfunction should be closely monitored after receiving iodinated contrast media and should be treated as needed. PMID:25375985

  12. Efficient star formation in the spiral arms of M51

    NASA Technical Reports Server (NTRS)

    Lord, Steven D.; Young, Judith S.

    1990-01-01

    The molecular, neutral, and ionized hydrogen distributions in the Sbc galaxy M51 (NGC 5194) are compared. To estimate H2 surface densities observations of the CO (J = 1 - 0) transition were made in 60 positions out to a radius of 155 arcsec. Extinction-corrected H-alpha intensities were used to compute the detailed massive star formation rates (MSFRs) in the disk. Estimates of the gas surface density, the MSFR, and the ratio of these quantities, MSFR/sigma(p), were then examined. The spiral arms were found to exhibit an excess gas density, measuring between 1.4 and 1.6 times the interarm values at 45 arcsec resolution. The total (arm and interarm) gas content and massive star formation rates in concentric annuli in the disk of M51 were computed. The two quantities fall off together with radius, yielding a relatively constant MSFR/sigma(p) with radius. This behavior is not explained by current models of star formation in galactic disks.

  13. Three-Dimensional Computed Tomography as a Method for Finding Die Attach Voids in Diodes

    NASA Technical Reports Server (NTRS)

    Brahm, E. N.; Rolin, T. D.

    2010-01-01

    NASA analyzes electrical, electronic, and electromechanical (EEE) parts used in space vehicles to understand failure modes of these components. The diode is an EEE part critical to NASA missions that can fail due to excessive voiding in the die attach. Metallography, one established method for studying the die attach, is a time-intensive, destructive, and equivocal process whereby mechanical grinding of the diodes is performed to reveal voiding in the die attach. Problems such as die attach pull-out tend to complicate results and can lead to erroneous conclusions. The objective of this study is to determine if three-dimensional computed tomography (3DCT), a nondestructive technique, is a viable alternative to metallography for detecting die attach voiding. The die attach voiding in two- dimensional planes created from 3DCT scans was compared to several physical cross sections of the same diode to determine if the 3DCT scan accurately recreates die attach volumetric variability

  14. Automatic summary generating technology of vegetable traceability for information sharing

    NASA Astrophysics Data System (ADS)

    Zhenxuan, Zhang; Minjing, Peng

    2017-06-01

    In order to solve problems of excessive data entries and consequent high costs for data collection in vegetable traceablility for farmers in traceability applications, the automatic summary generating technology of vegetable traceability for information sharing was proposed. The proposed technology is an effective way for farmers to share real-time vegetable planting information in social networking platforms to enhance their brands and obtain more customers. In this research, the influencing factors in the vegetable traceablility for customers were analyzed to establish the sub-indicators and target indicators and propose a computing model based on the collected parameter values of the planted vegetables and standard legal systems on food safety. The proposed standard parameter model involves five steps: accessing database, establishing target indicators, establishing sub-indicators, establishing standard reference model and computing scores of indicators. On the basis of establishing and optimizing the standards of food safety and traceability system, this proposed technology could be accepted by more and more farmers and customers.

  15. The passage of an infinite swept airfoil through an oblique gust. [approximate solution for aerodynamic response

    NASA Technical Reports Server (NTRS)

    Adamczyk, J. L.

    1974-01-01

    An approximate solution is reported for the unsteady aerodynamic response of an infinite swept wing encountering a vertical oblique gust in a compressible stream. The approximate expressions are of closed form and do not require excessive computer storage or computation time, and further, they are in good agreement with the results of exact theory. This analysis is used to predict the unsteady aerodynamic response of a helicopter rotor blade encountering the trailing vortex from a previous blade. Significant effects of three dimensionality and compressibility are evident in the results obtained. In addition, an approximate solution for the unsteady aerodynamic forces associated with the pitching or plunging motion of a two dimensional airfoil in a subsonic stream is presented. The mathematical form of this solution approaches the incompressible solution as the Mach number vanishes, the linear transonic solution as the Mach number approaches one, and the solution predicted by piston theory as the reduced frequency becomes large.

  16. Digital Mammography with a Mosaic of CCD-Arrays

    NASA Technical Reports Server (NTRS)

    Jalink, Antony, Jr. (Inventor); McAdoo, James A. (Inventor)

    1996-01-01

    The present invention relates generally to a mammography device and method and more particularly to a novel digital mammography device and method to detect microcalcifications of precancerous tissue. A digital mammography device uses a mosaic of electronic digital imaging arrays to scan an x-ray image. The mosaic of arrays is repositioned several times to expose different portions of the image, until the entire image is scanned. The data generated by the arrays during each exposure is stored in a computer. After the final exposure, the computer combines data of the several partial images to produce a composite of the original x-ray image. An aperture plate is used to reduce scatter and the overall exposure of the patient to x-rays. The novelty of this invention is that it provides a digital mammography device with large field coverage, high spatial resolution, scatter rejection, excellent contrast characteristics and lesion detectability under clinical conditions. This device also shields the patient from excessive radiation, can detect extremely small calcifications and allows manipulation and storage of the image.

  17. Micro-CT image reconstruction based on alternating direction augmented Lagrangian method and total variation.

    PubMed

    Gopi, Varun P; Palanisamy, P; Wahid, Khan A; Babyn, Paul; Cooper, David

    2013-01-01

    Micro-computed tomography (micro-CT) plays an important role in pre-clinical imaging. The radiation from micro-CT can result in excess radiation exposure to the specimen under test, hence the reduction of radiation from micro-CT is essential. The proposed research focused on analyzing and testing an alternating direction augmented Lagrangian (ADAL) algorithm to recover images from random projections using total variation (TV) regularization. The use of TV regularization in compressed sensing problems makes the recovered image quality sharper by preserving the edges or boundaries more accurately. In this work TV regularization problem is addressed by ADAL which is a variant of the classic augmented Lagrangian method for structured optimization. The per-iteration computational complexity of the algorithm is two fast Fourier transforms, two matrix vector multiplications and a linear time shrinkage operation. Comparison of experimental results indicate that the proposed algorithm is stable, efficient and competitive with the existing algorithms for solving TV regularization problems. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Unsteady Probabilistic Analysis of a Gas Turbine System

    NASA Technical Reports Server (NTRS)

    Brown, Marilyn

    2003-01-01

    In this work, we have considered an annular cascade configuration subjected to unsteady inflow conditions. The unsteady response calculation has been implemented into the time marching CFD code, MSUTURBO. The computed steady state results for the pressure distribution demonstrated good agreement with experimental data. We have computed results for the amplitudes of the unsteady pressure over the blade surfaces. With the increase in gas turbine engine structural complexity and performance over the past 50 years, structural engineers have created an array of safety nets to ensure against component failures in turbine engines. In order to reduce what is now considered to be excessive conservatism and yet maintain the same adequate margins of safety, there is a pressing need to explore methods of incorporating probabilistic design procedures into engine development. Probabilistic methods combine and prioritize the statistical distributions of each design variable, generate an interactive distribution and offer the designer a quantified relationship between robustness, endurance and performance. The designer can therefore iterate between weight reduction, life increase, engine size reduction, speed increase etc.

  19. Large eddy simulation of fine water sprays: comparative analysis of two models and computer codes

    NASA Astrophysics Data System (ADS)

    Tsoy, A. S.; Snegirev, A. Yu.

    2015-09-01

    The model and the computer code FDS, albeit widely used in engineering practice to predict fire development, is not sufficiently validated for fire suppression by fine water sprays. In this work, the effect of numerical resolution of the large scale turbulent pulsations on the accuracy of predicted time-averaged spray parameters is evaluated. Comparison of the simulation results obtained with the two versions of the model and code, as well as that of the predicted and measured radial distributions of the liquid flow rate revealed the need to apply monotonic and yet sufficiently accurate discrete approximations of the convective terms. Failure to do so delays jet break-up, otherwise induced by large turbulent eddies, thereby excessively focuses the predicted flow around its axis. The effect of the pressure drop in the spray nozzle is also examined, and its increase has shown to cause only weak increase of the evaporated fraction and vapor concentration despite the significant increase of flow velocity.

  20. Enhancement web proxy cache performance using Wrapper Feature Selection methods with NB and J48

    NASA Astrophysics Data System (ADS)

    Mahmoud Al-Qudah, Dua'a.; Funke Olanrewaju, Rashidah; Wong Azman, Amelia

    2017-11-01

    Web proxy cache technique reduces response time by storing a copy of pages between client and server sides. If requested pages are cached in the proxy, there is no need to access the server. Due to the limited size and excessive cost of cache compared to the other storages, cache replacement algorithm is used to determine evict page when the cache is full. On the other hand, the conventional algorithms for replacement such as Least Recently Use (LRU), First in First Out (FIFO), Least Frequently Use (LFU), Randomized Policy etc. may discard important pages just before use. Furthermore, using conventional algorithm cannot be well optimized since it requires some decision to intelligently evict a page before replacement. Hence, most researchers propose an integration among intelligent classifiers and replacement algorithm to improves replacement algorithms performance. This research proposes using automated wrapper feature selection methods to choose the best subset of features that are relevant and influence classifiers prediction accuracy. The result present that using wrapper feature selection methods namely: Best First (BFS), Incremental Wrapper subset selection(IWSS)embedded NB and particle swarm optimization(PSO)reduce number of features and have a good impact on reducing computation time. Using PSO enhance NB classifier accuracy by 1.1%, 0.43% and 0.22% over using NB with all features, using BFS and using IWSS embedded NB respectively. PSO rises J48 accuracy by 0.03%, 1.91 and 0.04% over using J48 classifier with all features, using IWSS-embedded NB and using BFS respectively. While using IWSS embedded NB fastest NB and J48 classifiers much more than BFS and PSO. However, it reduces computation time of NB by 0.1383 and reduce computation time of J48 by 2.998.

  1. Simulation of Propellant Loading System Senior Design Implement in Computer Algorithm

    NASA Technical Reports Server (NTRS)

    Bandyopadhyay, Alak

    2010-01-01

    Propellant loading from the Storage Tank to the External Tank is one of the very important and time consuming pre-launch ground operations for the launch vehicle. The propellant loading system is a complex integrated system involving many physical components such as the storage tank filled with cryogenic fluid at a very low temperature, the long pipe line connecting the storage tank with the external tank, the external tank along with the flare stack, and vent systems for releasing the excess fuel. Some of the very important parameters useful for design purpose are the prediction of pre-chill time, loading time, amount of fuel lost, the maximum pressure rise etc. The physics involved for mathematical modeling is quite complex due to the fact the process is unsteady, there is phase change as some of the fuel changes from liquid to gas state, then conjugate heat transfer in the pipe walls as well as between solid-to-fluid region. The simulation is very tedious and time consuming too. So overall, this is a complex system and the objective of the work is student's involvement and work in the parametric study and optimization of numerical modeling towards the design of such system. The students have to first become familiar and understand the physical process, the related mathematics and the numerical algorithm. The work involves exploring (i) improved algorithm to make the transient simulation computationally effective (reduced CPU time) and (ii) Parametric study to evaluate design parameters by changing the operational conditions

  2. Molecular Gibbs Surface Excess and CO2-Hydrate Density Determine the Strong Temperature- and Pressure-Dependent Supercritical CO2-Brine Interfacial Tension.

    PubMed

    Ji, Jiayuan; Zhao, Lingling; Tao, Lu; Lin, Shangchao

    2017-06-29

    In CO 2 geological storage, the interfacial tension (IFT) between supercritical CO 2 and brine is critical for the storage capacitance design to prevent CO 2 leakage. IFT relies not only on the interfacial molecule properties but also on the environmental conditions at different storage sites. In this paper, supercritical CO 2 -NaCl solution systems are modeled at 343-373 K and 6-35 MPa under the salinity of 1.89 mol/L using molecular dynamics simulations. After computing and comparing the molecular density profile across the interface, the atomic radial distribution function, the molecular orientation distribution, the molecular Gibbs surface excess (derived from the molecular density profile), and the CO 2 -hydrate number density under the above environmental conditions, we confirm that only the molecular Gibbs surface excess of CO 2 molecules and the CO 2 -hydrate number density correlate strongly with the temperature- and pressure-dependent IFTs. We also compute the populations of two distinct CO 2 -hydrate structures (T-type and H-type) and attribute the observed dependence of IFTs to the dominance of the more stable, surfactant-like T-type CO 2 -hydrates at the interface. On the basis of these new molecular mechanisms behind IFT variations, this study could guide the rational design of suitable injecting environmental pressure and temperature conditions. We believe that the above two molecular-level metrics (Gibbs surface excess and hydrate number density) are of great fundamental importance for understanding the supercritical CO 2 -water interface and engineering applications in geological CO 2 storage.

  3. Approximate factorization for incompressible flow. Ph.D. Thesis; [Navier-Stokes equation

    NASA Technical Reports Server (NTRS)

    Bernard, R. S.

    1981-01-01

    For computational solution of the incompressible Navier-Stokes equations, the approximate factorization (AF) algorithm is used to solve the vectorized momentum equation in delta form based on the pressure calculated in the previous time step. The newly calculated velocities are substituted into the pressure equation (obtained from a linear combination of the continuity and momentum equation), which is then solved by means of line SOR. Computational results are presented for the NACA 66 sub 3 018 airfoil at Reynolds numbers of 1000 and 40,000 and attack angles of 0 and 6 degrees. Comparison with wind tunnel data for Re = 40,000 indicates good qualitative agreement between measured and calculated pressure distributions. Quantitative agreement is only fair, however, with the calculations somewhat displaced from the measurements. Furthermore, the computed velocity profiles are unrealistically thick around the airfoil, due to the excessive amount of artificial viscosity needed for stability. Based on the performance of the algorithm with regard to stability, it is concluded that AF/SOR is suitable for calculations at Reynolds numbers less than 10,000. Speedwise, the method is faster than point SOR by at least a factor of two.

  4. Statistical aspects of solar flares

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    1987-01-01

    A survey of the statistical properties of 850 H alpha solar flares during 1975 is presented. Comparison of the results found here with those reported elsewhere for different epochs is accomplished. Distributions of rise time, decay time, and duration are given, as are the mean, mode, median, and 90th percentile values. Proportions by selected groupings are also determined. For flares in general, mean values for rise time, decay time, and duration are 5.2 + or - 0.4 min, and 18.1 + or 1.1 min, respectively. Subflares, accounting for nearly 90 percent of the flares, had mean values lower than those found for flares of H alpha importance greater than 1, and the differences are statistically significant. Likewise, flares of bright and normal relative brightness have mean values of decay time and duration that are significantly longer than those computed for faint flares, and mass-motion related flares are significantly longer than non-mass-motion related flares. Seventy-three percent of the mass-motion related flares are categorized as being a two-ribbon flare and/or being accompanied by a high-speed dark filament. Slow rise time flares (rise time greater than 5 min) have a mean value for duration that is significantly longer than that computed for fast rise time flares, and long-lived duration flares (duration greater than 18 min) have a mean value for rise time that is significantly longer than that computed for short-lived duration flares, suggesting a positive linear relationship between rise time and duration for flares. Monthly occurrence rates for flares in general and by group are found to be linearly related in a positive sense to monthly sunspot number. Statistical testing reveals the association between sunspot number and numbers of flares to be significant at the 95 percent level of confidence, and the t statistic for slope is significant at greater than 99 percent level of confidence. Dependent upon the specific fit, between 58 percent and 94 percent of the variation can be accounted for with the linear fits. A statistically significant Northern Hemisphere flare excess (P less than 1 percent) was found, as was a Western Hemisphere excess (P approx 3 percent). Subflares were more prolific within 45 deg of central meridian (P less than 1 percent), while flares of H alpha importance or = 1 were more prolific near the limbs greater than 45 deg from central meridian; P approx 2 percent). Two-ribbon flares were more frequent within 45 deg of central meridian (P less than 1 percent). Slow rise time flares occurred more frequently in the western hemisphere (P approx 2 percent), as did short-lived duration flares (P approx 9 percent), but fast rise time flares were not preferentially distributed (in terms of east-west or limb-disk). Long-lived duration flares occurred more often within 45 deg 0 central meridian (P approx 7 percent). Mean durations for subflares and flares of H alpha importance or + 1, found within 45 deg of central meridian, are 14 percent and 70 percent, respectively, longer than those found for flares closer to the limb. As compared to flares occurring near cycle maximum, the flares of 1975 (near solar minimum) have mean values of rise time, decay time, and duration that are significantly shorter. A flare near solar maximum, on average, is about 1.6 times longer than one occurring near solar minimum.

  5. Associations between factors within the home setting and screen time among children aged 0–5 years: a cross-sectional study

    PubMed Central

    2012-01-01

    Background Excessive engagement in screen time has several immediate and long-term health implications among pre-school children. However, little is known about the factors that influence screen time in this age group. Therefore, the purpose of this study was to use the Ecologic Model of Sedentary Behavior as a guide to examine associations between intrapersonal, interpersonal, and physical environment factors within the home setting and screen time among pre-school children. Methods Participants were 746 pre-school children (≤ 5 years old) from the Kingston, Ontario, Canada area. From May to September, 2011, parents completed a questionnaire regarding several intrapersonal (child demographics), interpersonal (family demographics, parental cognitions, parental behavior), and physical environment (television, computer, or video games in the bedroom) factors within the home setting. Parents also reported the average amount of time per day their child spent watching television and playing video/computer games. Associations were examined using linear and logistic regression models. Results Most participants (93.7%) watched television and 37.9% played video/computer games. Several intrapersonal, interpersonal, and physical environment factors within the home setting were associated with screen time. More specifically, age, parental attitudes, parental barriers, parental descriptive norms, parental screen time, and having a television in the bedroom were positive predictors of screen time; whereas, parental education, parental income, and parental self-efficacy were negative predictors of screen time in the linear regression analysis. Collectively these variables explained 64.2% of the variance in screen time. Parental cognitive factors (self-efficacy, attitudes, barriers, descriptive norms) at the interpersonal level explained a large portion (37.9%) of this variance. Conclusions A large proportion of screen time in pre-school children was explained by factors within the home setting. Parental cognitive factors at the interpersonal level were of particular relevance. These findings suggest that interventions aiming to foster appropriate screen time habits in pre-school children may be most effective if they target parents for behavioral change. PMID:22823887

  6. Thermodynamical and excess thermoacoustical study on some monosaccharide (glucose) with enzyme amylase in aqueous media at 298.15 K

    NASA Astrophysics Data System (ADS)

    Nithiyanantham, S.; Palaniappan, L.

    2011-03-01

    Ultrasonic velocity (U), density (ρ) and viscosity (η) measurements have been carried out in three ternary mixtures of glucose with amylase in aqueous medium at 298.15 K. The experimental data have been used to calculate some derived parameters such as acoustical impedance (Z), relative association (RA), Rao's constant (R), Wada's constant (W), relaxation time (τ), relaxation amplitude (α/f2), relaxation strength (r), and some excess thermodynamical properties like excess adiabatic compressibility (βE), excess free length (LfE) excess free volume (VfE), excess internal pressure (πiE) and excess acoustical impedance (ZE). The above parameters have been evaluated and discussed in light of molecular interactions in the mixture.

  7. A General Application Computer-Assisted Instruction System for Microcomputers.

    DTIC Science & Technology

    1987-09-01

    question pages. Variable branching is allowed from question pages depending on student answer input. Lesson size (i.e., number of vi 15511P11’P,6i 1111 kcj5...stocks, maldistribution of stocks, and accumulation and disposal of excess stocks. [ 10 :Appendix, 1]. These deficiencies also indicate a loss of...operations. 1- 10 II. Literature Review The computer is incredibly fast, accurate, and stupid. Man is unbelievably slow, inaccurate, and brilliant. The

  8. Ultralow 1/f Noise in a Heterostructure of Superconducting Epitaxial Cobalt Disilicide Thin Film on Silicon.

    PubMed

    Chiu, Shao-Pin; Yeh, Sheng-Shiuan; Chiou, Chien-Jyun; Chou, Yi-Chia; Lin, Juhn-Jong; Tsuei, Chang-Chyi

    2017-01-24

    High-precision resistance noise measurements indicate that the epitaxial CoSi 2 /Si heterostructures at 150 and 2 K (slightly above its superconducting transition temperature T c of 1.54 K) exhibit an unusually low 1/f noise level in the frequency range of 0.008-0.2 Hz. This corresponds to an upper limit of Hooge constant γ ≤ 3 × 10 -6 , about 100 times lower than that of single-crystalline aluminum films on SiO 2 capped Si substrates. Supported by high-resolution cross-sectional transmission electron microscopy studies, our analysis reveals that the 1/f noise is dominated by excess interfacial Si atoms and their dimer reconstruction induced fluctuators. Unbonded orbitals (i.e., dangling bonds) on excess Si atoms are intrinsically rare at the epitaxial CoSi 2 /Si(100) interface, giving limited trapping-detrapping centers for localized charges. With its excellent normal-state properties, CoSi 2 has been used in silicon-based integrated circuits for decades. The intrinsically low noise properties discovered in this work could be utilized for developing quiet qubits and scalable superconducting circuits for future quantum computing.

  9. Weighting Statistical Inputs for Data Used to Support Effective Decision Making During Severe Emergency Weather and Environmental Events

    NASA Technical Reports Server (NTRS)

    Gardner, Adrian

    2010-01-01

    National Aeronautical and Space Administration (NASA) weather and atmospheric environmental organizations are insatiable consumers of geophysical, hydrometeorological and solar weather statistics. The expanding array of internet-worked sensors producing targeted physical measurements has generated an almost factorial explosion of near real-time inputs to topical statistical datasets. Normalizing and value-based parsing of such statistical datasets in support of time-constrained weather and environmental alerts and warnings is essential, even with dedicated high-performance computational capabilities. What are the optimal indicators for advanced decision making? How do we recognize the line between sufficient statistical sampling and excessive, mission destructive sampling ? How do we assure that the normalization and parsing process, when interpolated through numerical models, yields accurate and actionable alerts and warnings? This presentation will address the integrated means and methods to achieve desired outputs for NASA and consumers of its data.

  10. [Smartphone usage among adolescents].

    PubMed

    Körmendi, Attila

    2015-01-01

    Among our technological gadgets smartphones play the most important role, new generation devices offer other functions beyond calling (internet availability, computer games, music player, camera functions etc.) In everydays can be experienced that youth spend more and more time with their smartphones and despite the actuality of this issue there are no studies on the excessive smartphone usage in Hungary and we can find only a few international studies. Our goal is to examine smartphone usage in primary and secondary schools in Hajdu-Bihar county, Hungary and its relationship with personality traits. Our sample consist of 263 youth from primary and secondary schools. We measured the characteristics of smartphone using and attitudes with a Mobilephone Using Questionnare. Personality traits are measured with Impulsiveness, Venturesomeness, Empathy Scale. The Child Behavior Checklist gives information about peer relationships, mental state and emotions. Average phone using time is 4,48 hours per day regarding the whole sample. This mean for boys is 3,40 hour for girls 5,39 hour. Average phone using time is higher at 16 (6,35 hour per day). The most frequent used applications are calling and visiting community sites. There is no connection between phone using and grades. The smartphone using time per day shows a significant positive relationship with Impulsivity, Anxiety and Depression, Attention deficits and Somatic problems within 17-19 ages. One of the explanation of excessive smartphone using may be the frequent visiting of community sites. Mobile phones in this case raise the availability of addictive object (community site) therefore contribute to the development of community site addiction. The connection with impulsivity, somatic problems and attention deficits refer to the anxiety reducing role of smartphones within 17-19 ages.

  11. Sodium Ion Diffusion in Nasicon (Na3Zr2Si2PO12) Solid Electrolytes: Effects of Excess Sodium.

    PubMed

    Park, Heetaek; Jung, Keeyoung; Nezafati, Marjan; Kim, Chang-Soo; Kang, Byoungwoo

    2016-10-04

    The Na superionic conductor (aka Nasicon, Na 1+x Zr 2 Si x P 3-x O 12 , where 0 ≤ x ≤ 3) is one of the promising solid electrolyte materials used in advanced molten Na-based secondary batteries that typically operate at high temperature (over ∼270 °C). Nasicon provides a 3D diffusion network allowing the transport of the active Na-ion species (i.e., ionic conductor) while blocking the conduction of electrons (i.e., electronic insulator) between the anode and cathode compartments of cells. In this work, the standard Nasicon (Na 3 Zr 2 Si 2 PO 12 , bare sample) and 10 at% Na-excess Nasicon (Na 3.3 Zr 2 Si 2 PO 12 , Na-excess sample) solid electrolytes were synthesized using a solid-state sintering technique to elucidate the Na diffusion mechanism (i.e., grain diffusion or grain boundary diffusion) and the impacts of adding excess Na at relatively low and high temperatures. The structural, thermal, and ionic transport characterizations were conducted using various experimental tools including X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). In addition, an ab initio atomistic modeling study was carried out to computationally examine the detailed microstructures of Nasicon materials, as well as to support the experimental observations. Through this combination work comprising experimental and computational investigations, we show that the predominant mechanisms of Na-ion transport in the Nasicon structure are the grain boundary and the grain diffusion at low and high temperatures, respectively. Also, it was found that adding 10 at% excess Na could give rise to a substantial increase in the total conductivity (e.g., ∼1.2 × 10 -1 S/cm at 300 °C) of Nasicon electrolytes resulting from the enlargement of the bottleneck areas in the Na diffusion channels of polycrystalline grains.

  12. A Summary Description of a Computer Program Concept for the Design and Simulation of Solar Pond Electric Power Generation Systems

    NASA Technical Reports Server (NTRS)

    1984-01-01

    A solar pond electric power generation subsystem, an electric power transformer and switch yard, a large solar pond, a water treatment plant, and numerous storage and evaporation ponds. Because a solar pond stores thermal energy over a long period of time, plant operation at any point in time is dependent upon past operation and future perceived generation plans. This time or past history factor introduces a new dimension in the design process. The design optimization of a plant must go beyond examination of operational state points and consider the seasonal variations in solar, solar pond energy storage, and desired plant annual duty-cycle profile. Models or design tools will be required to optimize a plant design. These models should be developed in order to include a proper but not excessive level of detail. The model should be targeted to a specific objective and not conceived as a do everything analysis tool, i.e., system design and not gradient-zone stability.

  13. SELECTION AND CALIBRATION OF SUBSURFACE REACTIVE TRANSPORT MODELS USING A SURROGATE-MODEL APPROACH

    EPA Science Inventory

    While standard techniques for uncertainty analysis have been successfully applied to groundwater flow models, extension to reactive transport is frustrated by numerous difficulties, including excessive computational burden and parameter non-uniqueness. This research introduces a...

  14. [Association between hours of television watched, physical activity, sleep and excess weight among young adults].

    PubMed

    Martínez-Moyá, María; Navarrete-Muñoz, Eva M; García de la Hera, Manuela; Giménez-Monzo, Daniel; González-Palacios, Sandra; Valera-Gran, Desirée; Sempere-Orts, María; Vioque, Jesús

    2014-01-01

    To explore the association between excess weight or body mass index (BMI) and the time spent watching television, self-reported physical activity and sleep duration in a young adult population. We analyzed cross-sectional baseline data of 1,135 participants (17-35 years old) from the project Dieta, salud y antropometría en población universitaria (Diet, Health and Anthrompmetric Variables in Univeristy Students). Information about time spent watching television, sleep duration, self-reported physical activity and self-reported height and weight was provided by a baseline questionnaire. BMI was calculated as kg/m(2) and excess of weight was defined as ≥25. We used multiple logistic regression to explore the association between excess weight (no/yes) and independent variables, and multiple linear regression for BMI. The prevalence of excess weight was 13.7% (11.2% were overweight and 2.5% were obese). A significant positive association was found between excess weight and a greater amount of time spent watching television. Participants who reported watching television >2h a day had a higher risk of excess weight than those who watched television ≤1h a day (OR=2.13; 95%CI: 1.37-3.36; p-trend: 0.002). A lower level of physical activity was associated with an increased risk of excess weight, although the association was statistically significant only in multiple linear regression (p=0.037). No association was observed with sleep duration. A greater number of hours spent watching television and lower physical activity were significantly associated with a higher BMI in young adults. Both factors are potentially modifiable with preventive strategies. Copyright © 2013 SESPAS. Published by Elsevier Espana. All rights reserved.

  15. DAMPE electron-positron excess in leptophilic Z' model

    NASA Astrophysics Data System (ADS)

    Ghorbani, Karim; Ghorbani, Parsa Hossein

    2018-05-01

    Recently the DArk Matter Particle Explorer (DAMPE) has reported an excess in the electron-positron flux of the cosmic rays which is interpreted as a dark matter particle with the mass about 1.5 TeV. We come up with a leptophilic Z' scenario including a Dirac fermion dark matter candidate which beside explaining the observed DAMPE excess, is able to pass various experimental/observational constraints including the relic density value from the WMAP/Planck, the invisible Higgs decay bound at the LHC, the LEP bounds in electron-positron scattering, the muon anomalous magnetic moment constraint, Fermi-LAT data, and finally the direct detection experiment limits from the XENON1t/LUX. By computing the electron-positron flux produced from a dark matter with the mass about 1.5 TeV we show that the model predicts the peak observed by the DAMPE.

  16. Management of Excess Material in the Navys Real Time Reutilization Asset Management Facilities Needs Improvement

    DTIC Science & Technology

    2017-01-23

    operations for financial and supply chain management . ii │ DODIG-2017-043 ( Project No. D2016-D000RD-0052.000) Results in Brief Management of Excess...following page. Recommendations (cont’d) DODIG-2017-043 ( Project No. D2016-D000RD-0052.000) │ iii Recommendations Table Management Recommendations...No. DODIG-2017-043 J A N U A R Y 2 3 , 2 0 1 7 Management of Excess Material in the Navy’s Real-Time Reutilization Asset Management Facilities

  17. Preoperative fasting: knowledge and perceptions.

    PubMed

    Baril, Patrice; Portman, Harriet

    2007-10-01

    Preoperative patient fasting is an essential element of the patient preparation process, but patients may be fasting for excessive lengths of time. Investigators at one facility used semi-structured interviews to explore the knowledge and beliefs of patients, nurses, and anesthesia care providers regarding the practice of preoperative patient fasting. Findings indicate that some patients had excessive fasting times, and practitioners had erroneous perceptions about patient knowledge regarding the rationale for fasting and compliance with instructions. Clinicians expressed concern about the effects of excessive fasting but were reluctant to relax the policy.

  18. 7 CFR 735.106 - Excess storage and transferring of agricultural products.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Excess storage and transferring of agricultural... WAREHOUSE ACT Warehouse Licensing § 735.106 Excess storage and transferring of agricultural products. (a) If at any time a warehouse operator stores an agricultural product in a warehouse subject to a license...

  19. 7 CFR 735.106 - Excess storage and transferring of agricultural products.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Excess storage and transferring of agricultural... WAREHOUSE ACT Warehouse Licensing § 735.106 Excess storage and transferring of agricultural products. (a) If at any time a warehouse operator stores an agricultural product in a warehouse subject to a license...

  20. Estimate of Space Radiation-Induced Cancer Risks for International Space Station Orbits

    NASA Technical Reports Server (NTRS)

    Wu, Honglu; Atwell, William; Cucinotta, Francis A.; Yang, Chui-hsu

    1996-01-01

    Excess cancer risks from exposures to space radiation are estimated for various orbits of the International Space Station (ISS). Organ exposures are computed with the transport codes, BRYNTRN and HZETRN, and the computerized anatomical male and computerized anatomical female models. Cancer risk coefficients in the National Council on Radiation Protection and Measurements report No. 98 are used to generate lifetime excess cancer incidence and cancer mortality after a one-month mission to ISS. The generated data are tabulated to serve as a quick reference for assessment of radiation risk to astronauts on ISS missions.

  1. A Bayesian Interpretation of Data Trimming to Remove Excess Claims. Excess Claims and Data Trimming in the Context of Credibility Rating Procedures.

    DTIC Science & Technology

    1981-12-01

    Gisler, William S. Jewell* 1. Motivation In Ratemaking and in Experience Rating one is often confronted with the dileina of whether or not to fully...are greatly indebted to R. Schnieper who did all the numerical work on the ETE computer. 4 -, -2- 2. The Basic Model Throughout the paper we work...l )~1) f - (1-i0)po (xl) + ipe(X) 3. The Basic Problem As always in the credibility context our aim is to estimate ua(s) based on the observations of

  2. Hybrid deterministic/stochastic simulation of complex biochemical systems.

    PubMed

    Lecca, Paola; Bagagiolo, Fabio; Scarpa, Marina

    2017-11-21

    In a biological cell, cellular functions and the genetic regulatory apparatus are implemented and controlled by complex networks of chemical reactions involving genes, proteins, and enzymes. Accurate computational models are indispensable means for understanding the mechanisms behind the evolution of a complex system, not always explored with wet lab experiments. To serve their purpose, computational models, however, should be able to describe and simulate the complexity of a biological system in many of its aspects. Moreover, it should be implemented by efficient algorithms requiring the shortest possible execution time, to avoid enlarging excessively the time elapsing between data analysis and any subsequent experiment. Besides the features of their topological structure, the complexity of biological networks also refers to their dynamics, that is often non-linear and stiff. The stiffness is due to the presence of molecular species whose abundance fluctuates by many orders of magnitude. A fully stochastic simulation of a stiff system is computationally time-expensive. On the other hand, continuous models are less costly, but they fail to capture the stochastic behaviour of small populations of molecular species. We introduce a new efficient hybrid stochastic-deterministic computational model and the software tool MoBioS (MOlecular Biology Simulator) implementing it. The mathematical model of MoBioS uses continuous differential equations to describe the deterministic reactions and a Gillespie-like algorithm to describe the stochastic ones. Unlike the majority of current hybrid methods, the MoBioS algorithm divides the reactions' set into fast reactions, moderate reactions, and slow reactions and implements a hysteresis switching between the stochastic model and the deterministic model. Fast reactions are approximated as continuous-deterministic processes and modelled by deterministic rate equations. Moderate reactions are those whose reaction waiting time is greater than the fast reaction waiting time but smaller than the slow reaction waiting time. A moderate reaction is approximated as a stochastic (deterministic) process if it was classified as a stochastic (deterministic) process at the time at which it crosses the threshold of low (high) waiting time. A Gillespie First Reaction Method is implemented to select and execute the slow reactions. The performances of MoBios were tested on a typical example of hybrid dynamics: that is the DNA transcription regulation. The simulated dynamic profile of the reagents' abundance and the estimate of the error introduced by the fully deterministic approach were used to evaluate the consistency of the computational model and that of the software tool.

  3. Note on the coefficient of variations of neuronal spike trains.

    PubMed

    Lengler, Johannes; Steger, Angelika

    2017-08-01

    It is known that many neurons in the brain show spike trains with a coefficient of variation (CV) of the interspike times of approximately 1, thus resembling the properties of Poisson spike trains. Computational studies have been able to reproduce this phenomenon. However, the underlying models were too complex to be examined analytically. In this paper, we offer a simple model that shows the same effect but is accessible to an analytic treatment. The model is a random walk model with a reflecting barrier; we give explicit formulas for the CV in the regime of excess inhibition. We also analyze the effect of probabilistic synapses in our model and show that it resembles previous findings that were obtained by simulation.

  4. Estimating the Mechanical Behavior of the Knee Joint during Crouch Gait: Implications for Real-Time Motor Control of Robotic Knee Orthoses

    PubMed Central

    Damiano, Diane L.; Bulea, Thomas C.

    2016-01-01

    Individuals with cerebral palsy frequently exhibit crouch gait, a pathological walking pattern characterized by excessive knee flexion. Knowledge of the knee joint moment during crouch gait is necessary for the design and control of assistive devices used for treatment. Our goal was to 1) develop statistical models to estimate knee joint moment extrema and dynamic stiffness during crouch gait, and 2) use the models to estimate the instantaneous joint moment during weight-acceptance. We retrospectively computed knee moments from 10 children with crouch gait and used stepwise linear regression to develop statistical models describing the knee moment features. The models explained at least 90% of the response value variability: peak moment in early (99%) and late (90%) stance, and dynamic stiffness of weight-acceptance flexion (94%) and extension (98%). We estimated knee extensor moment profiles from the predicted dynamic stiffness and instantaneous knee angle. This approach captured the timing and shape of the computed moment (root-mean-squared error: 2.64 Nm); including the predicted early-stance peak moment as a correction factor improved model performance (root-mean-squared error: 1.37 Nm). Our strategy provides a practical, accurate method to estimate the knee moment during crouch gait, and could be used for real-time, adaptive control of robotic orthoses. PMID:27101612

  5. A detailed description of the short-term musculoskeletal and cognitive effects of prolonged standing for office computer work.

    PubMed

    Baker, Richelle; Coenen, Pieter; Howie, Erin; Lee, Jeremy; Williamson, Ann; Straker, Leon

    2018-07-01

    Due to concerns about excessive sedentary exposure for office workers, alternate work positions such as standing are being trialled. However, prolonged standing may have health and productivity impacts, which this study assessed. Twenty adult participants undertook two hours of laboratory-based standing computer work to investigate changes in discomfort and cognitive function, along with muscle fatigue, movement, lower limb swelling and mental state. Over time, discomfort increased in all body areas (total body IRR [95% confidence interval]: 1.47[1.36-1.59]). Sustained attention reaction time (β = 18.25[8.00-28.51]) deteriorated, while creative problem solving improved (β = 0.89[0.29-1.49]). There was no change in erector spinae, rectus femoris, biceps femoris or tibialis anterior muscle fatigue; low back angle changed towards less  lordosis, pelvis movement increased, lower limb swelling increased and mental state decreased. Body discomfort was positively correlated with mental state. The observed changes suggest replacing office work sitting with standing should be done with caution. Practitioner Summary: Standing is being used to replace sitting by office workers; however, there are health risks associated with prolonged standing. In a laboratory study involving 2 h prolonged standing discomfort increased (all body areas), reaction time and mental state deteriorated while creative problem-solving improved. Prolonged standing should be undertaken with caution.

  6. Calculating excess lifetime risk in relative risk models.

    PubMed Central

    Vaeth, M; Pierce, D A

    1990-01-01

    When assessing the impact of radiation exposure it is common practice to present the final conclusions in terms of excess lifetime cancer risk in a population exposed to a given dose. The present investigation is mainly a methodological study focusing on some of the major issues and uncertainties involved in calculating such excess lifetime risks and related risk projection methods. The age-constant relative risk model used in the recent analyses of the cancer mortality that was observed in the follow-up of the cohort of A-bomb survivors in Hiroshima and Nagasaki is used to describe the effect of the exposure on the cancer mortality. In this type of model the excess relative risk is constant in age-at-risk, but depends on the age-at-exposure. Calculation of excess lifetime risks usually requires rather complicated life-table computations. In this paper we propose a simple approximation to the excess lifetime risk; the validity of the approximation for low levels of exposure is justified empirically as well as theoretically. This approximation provides important guidance in understanding the influence of the various factors involved in risk projections. Among the further topics considered are the influence of a latent period, the additional problems involved in calculations of site-specific excess lifetime cancer risks, the consequences of a leveling off or a plateau in the excess relative risk, and the uncertainties involved in transferring results from one population to another. The main part of this study relates to the situation with a single, instantaneous exposure, but a brief discussion is also given of the problem with a continuous exposure at a low-dose rate. PMID:2269245

  7. Calculating excess lifetime risk in relative risk models.

    PubMed

    Vaeth, M; Pierce, D A

    1990-07-01

    When assessing the impact of radiation exposure it is common practice to present the final conclusions in terms of excess lifetime cancer risk in a population exposed to a given dose. The present investigation is mainly a methodological study focusing on some of the major issues and uncertainties involved in calculating such excess lifetime risks and related risk projection methods. The age-constant relative risk model used in the recent analyses of the cancer mortality that was observed in the follow-up of the cohort of A-bomb survivors in Hiroshima and Nagasaki is used to describe the effect of the exposure on the cancer mortality. In this type of model the excess relative risk is constant in age-at-risk, but depends on the age-at-exposure. Calculation of excess lifetime risks usually requires rather complicated life-table computations. In this paper we propose a simple approximation to the excess lifetime risk; the validity of the approximation for low levels of exposure is justified empirically as well as theoretically. This approximation provides important guidance in understanding the influence of the various factors involved in risk projections. Among the further topics considered are the influence of a latent period, the additional problems involved in calculations of site-specific excess lifetime cancer risks, the consequences of a leveling off or a plateau in the excess relative risk, and the uncertainties involved in transferring results from one population to another. The main part of this study relates to the situation with a single, instantaneous exposure, but a brief discussion is also given of the problem with a continuous exposure at a low-dose rate.

  8. A Survey of X-Ray Variability in Seyfert 1 Galaxies with XMM-Newton to study the soft excess and the broad Fe lines

    NASA Astrophysics Data System (ADS)

    Ponti, Gabriele

    The nature of the soft excess and the presence of the broad Fe lines is still nowadays highly debated because the different absorption/emission models are degenerate. Spectral variability studies have the potential to break this degeneracy. I will present the results of a spectral variability RMS survey of the 36 brightest type 1 Seyfert galaxies observed by XMM-Newton for more than 30 ks. More than 80 as already measured, on longer timescales, with RXTE (Markowitz et al. 2004). About half of the sample show lower variability in the soft energy band, indicating that the emission from the soft excess is more stable than the one of the continuum. While the other sources show a soft excess that is as variable as the continuum. About half of the sample do not show an excess of variability where the warm absorber component imprints its stronger features, suggesting that for these sources the soft excess is not produced by a relativistic absorbing wind. In a few bright and well exposed sources it has been possible to measure an excess of variability at the energy of the broad component of the Fe K line, in agreement with the broad emission line interpretation. For the sources where more than one observation was available the stability of the shape of the RMS spectrum has been investigated. Moreover, it will be presented the results of the computation of the excess variance of all the radio quiet type 1 AGN of the XMM-Newton database. The relations between variability, black hole mass, accretion rate and luminosity are investigated and their scatter measured.

  9. Mycotoxin Management Studies by USDA-"Ag Lab" in 2008

    USDA-ARS?s Scientific Manuscript database

    Studies again included several popcorn fields in 2008, in order to continue gathering data for modification of the previously developed management strategies for mycotoxins in field corn (the mycotoxin predictive computer program). Weather conditions were generally good for growing corn, but excess...

  10. 78 FR 72451 - Net Investment Income Tax

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-02

    ... Net Investment Income Tax AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Withdrawal of... computation of net investment income. The regulations affect individuals, estates, and trusts whose incomes... investment income for such taxable year, or (B) the excess (if any) of: (i) The individual's modified...

  11. Robust crop and weed segmentation under uncontrolled outdoor illumination

    USDA-ARS?s Scientific Manuscript database

    A new machine vision for weed detection was developed from RGB color model images. Processes included in the algorithm for the detection were excessive green conversion, threshold value computation by statistical analysis, adaptive image segmentation by adjusting the threshold value, median filter, ...

  12. A Computational Framework to Optimize Subject-Specific Hemodialysis Blood Flow Rate to Prevent Intimal Hyperplasia

    NASA Astrophysics Data System (ADS)

    Mahmoudzadeh, Javid; Wlodarczyk, Marta; Cassel, Kevin

    2017-11-01

    Development of excessive intimal hyperplasia (IH) in the cephalic vein of renal failure patients who receive chronic hemodialysis treatment results in vascular access failure and multiple treatment complications. Specifically, cephalic arch stenosis (CAS) is known to exacerbate hypertensive blood pressure, thrombosis, and subsequent cardiovascular incidents that would necessitate costly interventional procedures with low success rates. It has been hypothesized that excessive blood flow rate post access maturation which strongly violates the venous homeostasis is the main hemodynamic factor that orchestrates the onset and development of CAS. In this article, a computational framework based on a strong coupling of computational fluid dynamics (CFD) and shape optimization is proposed that aims to identify the effective blood flow rate on a patient-specific basis that avoids the onset of CAS while providing the adequate blood flow rate required to facilitate hemodialysis. This effective flow rate can be achieved through implementation of Miller's surgical banding method after the maturation of the arteriovenous fistula and is rooted in the relaxation of wall stresses back to a homeostatic target value. The results are indicative that this optimized hemodialysis blood flow rate is, in fact, a subject-specific value that can be assessed post vascular access maturation and prior to the initiation of chronic hemodialysis treatment as a mitigative action against CAS-related access failure. This computational technology can be employed for individualized dialysis treatment.

  13. A new look at the simultaneous analysis and design of structures

    NASA Technical Reports Server (NTRS)

    Striz, Alfred G.

    1994-01-01

    The minimum weight optimization of structural systems, subject to strength and displacement constraints as well as size side constraints, was investigated by the Simultaneous ANalysis and Design (SAND) approach. As an optimizer, the code NPSOL was used which is based on a sequential quadratic programming (SQP) algorithm. The structures were modeled by the finite element method. The finite element related input to NPSOL was automatically generated from the input decks of such standard FEM/optimization codes as NASTRAN or ASTROS, with the stiffness matrices, at present, extracted from the FEM code ANALYZE. In order to avoid ill-conditioned matrices that can be encountered when the global stiffness equations are used as additional nonlinear equality constraints in the SAND approach (with the displacements as additional variables), the matrix displacement method was applied. In this approach, the element stiffness equations are used as constraints instead of the global stiffness equations, in conjunction with the nodal force equilibrium equations. This approach adds the element forces as variables to the system. Since, for complex structures and the associated large and very sparce matrices, the execution times of the optimization code became excessive due to the large number of required constraint gradient evaluations, the Kreisselmeier-Steinhauser function approach was used to decrease the computational effort by reducing the nonlinear equality constraint system to essentially a single combined constraint equation. As the linear equality and inequality constraints require much less computational effort to evaluate, they were kept in their previous form to limit the complexity of the KS function evaluation. To date, the standard three-bar, ten-bar, and 72-bar trusses have been tested. For the standard SAND approach, correct results were obtained for all three trusses although convergence became slower for the 72-bar truss. When the matrix displacement method was used, correct results were still obtained, but the execution times became excessive due to the large number of constraint gradient evaluations required. Using the KS function, the computational effort dropped, but the optimization seemed to become less robust. The investigation of this phenomenon is continuing. As an alternate approach, the code MINOS for the optimization of sparse matrices can be applied to the problem in lieu of the Kreisselmeier-Steinhauser function. This investigation is underway.

  14. THE NANOGRAV NINE-YEAR DATA SET: EXCESS NOISE IN MILLISECOND PULSAR ARRIVAL TIMES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lam, M. T.; Jones, M. L.; McLaughlin, M. A.

    Gravitational wave (GW) astronomy using a pulsar timing array requires high-quality millisecond pulsars (MSPs), correctable interstellar propagation delays, and high-precision measurements of pulse times of arrival. Here we identify noise in timing residuals that exceeds that predicted for arrival time estimation for MSPs observed by the North American Nanohertz Observatory for Gravitational Waves. We characterize the excess noise using variance and structure function analyses. We find that 26 out of 37 pulsars show inconsistencies with a white-noise-only model based on the short timescale analysis of each pulsar, and we demonstrate that the excess noise has a red power spectrum formore » 15 pulsars. We also decompose the excess noise into chromatic (radio-frequency-dependent) and achromatic components. Associating the achromatic red-noise component with spin noise and including additional power-spectrum-based estimates from the literature, we estimate a scaling law in terms of spin parameters (frequency and frequency derivative) and data-span length and compare it to the scaling law of Shannon and Cordes. We briefly discuss our results in terms of detection of GWs at nanohertz frequencies.« less

  15. A spatial-temporal approach to surveillance of prostate cancer disparities in population subgroups.

    PubMed Central

    Hsu, Chiehwen Ed; Mas, Francisco Soto; Miller, Jerry A.; Nkhoma, Ella T.

    2007-01-01

    BACKGROUND: Prostate cancer mortality disparities exist among racial/ethnic groups in the United States, yet few studies have explored the spatiotemporal trend of the disease burden. To better understand mortality disparities by geographic regions over time, the present study analyzed the geographic variations of prostate cancer mortality by three Texas racial/ethnic groups over a 22-year period. METHODS: The Spatial Scan Statistic developed by Kulldorff et al was used. Excess mortality was detected using scan windows of 50% and 90% of the study period and a spatial cluster size of 50% of the population at risk. Time trend was analyzed to examine the potential temporal effects of clustering. Spatial queries were used to identify regions with multiple racial/ethnic groups having excess mortality. RESULTS: The most likely area of excess mortality for blacks occurred in Dallas-Metroplex and upper east Texas areas between 1990 and 1999; for Hispanics, in central Texas between 1992 and 1996: and for non-Hispanic whites, in the upper south and west to central Texas areas between 1990 and 1996. Excess mortality persisted among all racial/ethnic groups in the identified counties. The second scan revealed that three counties in west Texas presented an excess mortality for Hispanics from 1980-2001. Many counties bore an excess mortality burden for multiple groups. There is no time trend decline in prostate cancer mortality for blacks and non-Hispanic whites in Texas. CONCLUSION: Disparities in prostate cancer mortality among racial/ethnic groups existed in Texas. Central Texas counties with excess mortality in multiple subgroups warrant further investigation. PMID:17304971

  16. 3D fast adaptive correlation imaging for large-scale gravity data based on GPU computation

    NASA Astrophysics Data System (ADS)

    Chen, Z.; Meng, X.; Guo, L.; Liu, G.

    2011-12-01

    In recent years, large scale gravity data sets have been collected and employed to enhance gravity problem-solving abilities of tectonics studies in China. Aiming at the large scale data and the requirement of rapid interpretation, previous authors have carried out a lot of work, including the fast gradient module inversion and Euler deconvolution depth inversion ,3-D physical property inversion using stochastic subspaces and equivalent storage, fast inversion using wavelet transforms and a logarithmic barrier method. So it can be say that 3-D gravity inversion has been greatly improved in the last decade. Many authors added many different kinds of priori information and constraints to deal with nonuniqueness using models composed of a large number of contiguous cells of unknown property and obtained good results. However, due to long computation time, instability and other shortcomings, 3-D physical property inversion has not been widely applied to large-scale data yet. In order to achieve 3-D interpretation with high efficiency and precision for geological and ore bodies and obtain their subsurface distribution, there is an urgent need to find a fast and efficient inversion method for large scale gravity data. As an entirely new geophysical inversion method, 3D correlation has a rapid development thanks to the advantage of requiring no a priori information and demanding small amount of computer memory. This method was proposed to image the distribution of equivalent excess masses of anomalous geological bodies with high resolution both longitudinally and transversely. In order to tranform the equivalence excess masses into real density contrasts, we adopt the adaptive correlation imaging for gravity data. After each 3D correlation imaging, we change the equivalence into density contrasts according to the linear relationship, and then carry out forward gravity calculation for each rectangle cells. Next, we compare the forward gravity data with real data, and comtinue to perform 3D correlation imaging for the redisual gravity data. After several iterations, we can obtain a satisfactoy results. Newly developed general purpose computing technology from Nvidia GPU (Graphics Processing Unit) has been put into practice and received widespread attention in many areas. Based on the GPU programming mode and two parallel levels, five CPU loops for the main computation of 3D correlation imaging are converted into three loops in GPU kernel functions, thus achieving GPU/CPU collaborative computing. The two inner loops are defined as the dimensions of blocks and the three outer loops are defined as the dimensions of threads, thus realizing the double loop block calculation. Theoretical and real gravity data tests show that results are reliable and the computing time is greatly reduced. Acknowledgments We acknowledge the financial support of Sinoprobe project (201011039 and 201011049-03), the Fundamental Research Funds for the Central Universities (2010ZY26 and 2011PY0183), the National Natural Science Foundation of China (41074095) and the Open Project of State Key Laboratory of Geological Processes and Mineral Resources (GPMR0945).

  17. No condylar lift-off occurs because of excessive lateral soft tissue laxity in neutrally aligned total knee arthroplasty: a computer simulation study.

    PubMed

    Kuriyama, Shinichi; Ishikawa, Masahiro; Nakamura, Shinichiro; Furu, Moritoshi; Ito, Hiromu; Matsuda, Shuichi

    2016-08-01

    Condylar lift-off can induce excessive polyethylene wear after total knee arthroplasty (TKA). A computer simulation was used to evaluate the influence of femoral varus alignment and lateral collateral ligament (LCL) laxity on lift-off after single-design TKA. It was hypothesised that proper ligament balancing and coronal alignment would prevent lift-off. The computer model in this study is a dynamic musculoskeletal program that simulates gait up to 60° of knee flexion. The lift-off phenomenon was defined as positive with an intercomponent distance of >2 mm. In neutrally aligned components in the coronal plane, the femoral and tibial components were set perpendicular to the femoral and tibial mechanical axis, respectively. The femoral coronal alignment was changed from neutral to 5° varus in 1° increments. Simultaneously, the LCL length was elongated from 0 to 5 mm in 1-mm increments to provide a model of pathological slack. Within 2° of femoral varus alignment, lift-off did not occur even if the LCL was elongated by up to 5 mm. However, lift-off occurred easily in the stance phase in femoral varus alignments of >3° with slight LCL slack. The contact forces of the tibiofemoral joint were influenced more by femoral varus alignment than by LCL laxity. Aiming for neutral alignment in severely varus knees makes it difficult to achieve appropriate ligament balance. Our study suggests that no lift-off occurs with excessive LCL laxity alone in a neutrally aligned TKA and therefore that varus alignment should be avoided to decrease lift-off after TKA. Case series, Level IV.

  18. Excess Noise Depletion of a Bose-Einstein Condensate in an Optical Cavity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Szirmai, G.; Nagy, D.; Domokos, P.

    2009-02-27

    Quantum fluctuations of a cavity field coupled into the motion of ultracold bosons can be strongly amplified by a mechanism analogous to the Petermann excess noise factor in lasers with unstable cavities. For a Bose-Einstein condensate in a stable optical resonator, the excess noise effect amounts to a significant depletion on long time scales.

  19. Investigation on molecular interactions of binary mixtures of isobutanol with 1-alkanols (C1 - C6) at different temperatures. Application of the Peng-Robinson-Stryjek-Vera (PSRV) equation of state (EOS)

    NASA Astrophysics Data System (ADS)

    Khanlarzadeh, K.; Iloukhani, H.; Soleimani, M.

    2017-07-01

    Densities were measured for binary mixtures of isobutanol with 1-alkanols, namely: methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol and 1-hexanol at the temperatures of (288.15, 298.15 and 308.15) K and ambient pressure. Excess molar volumes, VmE , thermal expansion coefficients α, excess thermal expansion coefficients αE, and isothermal coefficients of pressure excess molar enthalpy, (∂HmE / ∂ P) T , x , were derived from the experimental data and the computed results were fitted to the Redlich-Kister equation. The Peng-Robinson-Stryjek-Vera (PRSV) equation of state was applied, in combination with simple mixing rules to predict the excess molar volume. The VmE results were positive for the mixtures of isobutanol with methanol, ethanol, 1-propanol, 1-butanol, and negative for isobutanol with 1-pentanol and 1-hexanol over the whole composition range. The results showed very small deviations from the behavior of ideal solutions in these mixtures and were analyzed to discuss the nature and strength of intermolecular interactions.

  20. Video gaming and gender differences in digital and printed reading performance among 15-year-olds students in 26 countries.

    PubMed

    Borgonovi, Francesca

    2016-04-01

    Video games are a favorite leisure-time activity among teenagers worldwide. This study examines cross-national gender differences in reading achievement and video gaming and whether video gaming explains gender differences in reading achievement and differences in performance between paper-based and computer-based reading. We use data from a representative sample of 145,953 students from 26 countries who sat the PISA 2012 assessments and provided self-reports on use of video games. Although boys tend to have poorer results in both the computer-based and the paper-based reading assessments, boys' under achievement is smaller when the assessment is delivered on computer than when it is delivered on paper. Boys underperformance compared to girls in the two reading assessments is particularly pronounced among low-achieving students. Among both boys and girls moderate use of single-player games is associated with a performance advantage. However, frequent engagement with collaborative online games is generally associated with a steep reduction in achievement, particularly in the paper-based test and particularly among low-achieving students. Excessive gaming may hinder academic achievement, but moderate gaming can promote positive student outcomes. In many countries video gaming explains the difference in the gender gap in reading between the paper-based and the computer-based assessments. Copyright © 2016 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  1. The soft X-ray excess in Einstein quasar spectra

    NASA Technical Reports Server (NTRS)

    Masnou, J. L.; Wilkes, B. J.; Elvis, M.; Mcdowell, J. C.; Arnaud, K. A.

    1992-01-01

    An SNR-limited subsample of 14 quasars from the Wilkes and Elvis (1987) sample is presently investigated for low-energy excess above a high-energy power law in the X-ray spectra obtained by the Einstein Imaging Proportional Counter. A significant excess that is 1-6 times as strong as the high-energy component at 0.2 keV is noted in eight of the 14 objects. In the case of 3C273, multiple observations show the excess to be variable.

  2. Decomposition Algorithm for Global Reachability Analysis on a Time-Varying Graph with an Application to Planetary Exploration

    NASA Technical Reports Server (NTRS)

    Kuwata, Yoshiaki; Blackmore, Lars; Wolf, Michael; Fathpour, Nanaz; Newman, Claire; Elfes, Alberto

    2009-01-01

    Hot air (Montgolfiere) balloons represent a promising vehicle system for possible future exploration of planets and moons with thick atmospheres such as Venus and Titan. To go to a desired location, this vehicle can primarily use the horizontal wind that varies with altitude, with a small help of its own actuation. A main challenge is how to plan such trajectory in a highly nonlinear and time-varying wind field. This paper poses this trajectory planning as a graph search on the space-time grid and addresses its computational aspects. When capturing various time scales involved in the wind field over the duration of long exploration mission, the size of the graph becomes excessively large. We show that the adjacency matrix of the graph is block-triangular, and by exploiting this structure, we decompose the large planning problem into several smaller subproblems, whose memory requirement stays almost constant as the problem size grows. The approach is demonstrated on a global reachability analysis of a possible Titan mission scenario.

  3. The composition of bulk precipitation on a coastal island with agriculture compared to an urban region

    NASA Astrophysics Data System (ADS)

    Weijers, E. P.; Vugts, H. F.

    Results of chemical analyses of monthly bulk samples from Schiermonnikoog, one of the islands in the northern part of The Netherlands, are interpreted. The continuous record covers a period of more than 15 years. A comparison (10 years) is made with Ouderkerk, a village near Amsterdam. Non-sea salt contributions, relations between ion species, long-time trends, annual cycles and meteorological influence are discussed. The study reveals enhanced levels of ammonium in the Schiermonnikoog samples with respect to Ouderkerk. Also, concentrations of sulfate and nitrate were higher. The high concentrations of ammonium are ascribed to dry-deposited NH 3 caused by cattle breeding, the only economical activity on the island. A significant positive trend reflects its intensifying nature. Annual cycles and statistical computations indicate prior combination of parts of ammonium and excess sulfate as ammonium sulfate. The nitrate content appears to be strongly related to ammonium ( r = 079). In the Ouderkerk dataset this correspondence is much weaker (0.37), whereas its pH values are systematically lower. It is therefore believed that on Schiermonnikoog concentrations of nitrate are increased by nitrification of ammonium in the collector. Annual cycles of sodium, magnesium and chloride, and to a lesser extent potassium, are very similar (maximum concentrations in November, December and January, and a relative maximum in April). The other annual patterns peak in the first half of the year: maximum concentrations are found in February (ammonium, excess sulfate), June (nitrate), January (potassium) and in April (excess calcium). A combination of frequently occurring offshore winds and low precipitation amounts will account for this behavior.

  4. Mortality among members of a heavy construction equipment operators union with potential exposure to diesel exhaust emissions.

    PubMed Central

    Wong, O; Morgan, R W; Kheifets, L; Larson, S R; Whorton, M D

    1985-01-01

    A historical prospective mortality study was conducted on a cohort of 34 156 male members of a heavy construction equipment operators union with potential exposure to diesel exhaust emissions. This cohort comprised all individuals who were members of the International Union of Operating Engineers, Locals 3 and 3A, for at least one year between 1 January 1964 and 31 December 1978. The mortality experience of the entire cohort and several subcohorts was compared with that of United States white men, adjusted for age and calendar time. The comparison statistic was the commonly used standardised mortality ratio (SMR). Historical environmental measurements did not exist, but partial work histories were available for some cohort members through the union dispatch computer tapes. An attempt was made to relate mortality experience to the union members' dispatch histories. Overall mortality for the entire cohort and several subgroups was significantly lower than expected. When cause specific mortality was examined, however, the study provided suggestive evidence for the existence of several potential health problems in this cohort. Mortality from liver cancer for the entire cohort was significantly high. Although mortality from lung cancer for the entire cohort was similar to expected, a positive trend by latency was observed for lung cancer. A significant excess of mortality from lung cancer was found among the retirees and the group for whom no dispatch histories were available. Other dispatch groups showed no evidence of lung cancer excess. In addition, the total cohort experienced significant mortality excess from emphysema and accidental deaths. PMID:2410010

  5. Longitudinal associations between television in the bedroom and body fatness in a UK cohort study

    PubMed Central

    Heilmann, A; Rouxel, P; Fitzsimons, E; Kelly, Y; Watt, R G

    2017-01-01

    Objective: To assess longitudinal associations between screen-based media use (television (TV) and computer hours, having a TV in the bedroom) and body fatness among UK children. Methods: Participants were 12 556 children from the UK Millennium Cohort Study who were followed from age 7 to age 11 years. Associations were assessed between screen-based media use and the following outcomes: body mass index (BMI), fat mass index (FMI), and overweight. Results: In fully adjusted models, having a bedroom TV at age 7 years was associated with significantly higher BMI and FMI (excess BMI for boys=0.29, 95% confidence interval (CI) 0.06–0.52; excess BMI for girls=0.57, 95% CI 0.31–0.84; excess FMI for boys=0.20, 95% CI 0.04–0.37; excess FMI for girls=0.39, 95% CI 0.21–0.57) and increased risk of being overweight (relative risk (RR) for boys=1.21, 95% CI 1.07–1.36; RR for girls=1.31, 95% CI 1.15–1.48) at age 11 years, compared with having no bedroom TV. Hours spent watching TV or digital versatile disks were associated with increased risk of overweight among girls only. Computer use at age 7 years was not related to later body fatness for either gender. Conclusion: Having a TV in the child’s bedroom was an independent risk factor for overweight and increased body fatness in this nationally representative sample of UK children. Childhood obesity prevention strategies should consider TVs in children’s bedrooms as a risk factor for obesity. PMID:28566749

  6. Introduction of an operating room information management system improved overall operating room efficiency.

    PubMed

    De Deyne, Cathy; Heylen, René

    2004-01-01

    Operating Room (OR) information systems should manage the OR time, assigned to every surgeon, thereby minimizing the sum of costs of unused OR time and minimizing the costs of elective cases performed outside normal allocated OR time (excess OR-time). The aim of this paper is to illustrate how the introduction of an OR information system influenced daily OR activity performance. Since January 2001, we introduced an OR information system with a visual, airport-like, screen as central part, displaying all scheduled OR activity linked in real-time activity with all OR theatres. For the aim of this paper, we compared all data of OR activity for elective abdominal surgery (EAS) for the first half of 2000 compared to the first half of 2001, after the introduction of our information system. In 2000, 764 elective cases were performed, compared to 815 cases in 2001. For both periods, the total OR time allocated to EAS for this 6 months period was 805 h. For 2000, the total duration of OR activity for EAS was 1044 h 50 min (implicating 239 h 50 min over-time), compared to 1127 h 35 min (implicating 322 h 35 min overtime) for 2001. For 2000, we recorded 147 h 20 min excess time (=exceeding the time limits of OR activity and inducing extra costs) and 46h45min unused OR time. For 2001, we recorded 123 h 04 min excess time and 35 h 21 min unused time. In conclusion, in 2001 we recorded an increase in total OR activity for elective abdominal surgery by 7% in number of procedures and by 8% in total duration. However, in 2001 we recorded a decrease in excess time by 16% (123 h 04 min vs 147 h 20 min), which was for a large part due to a 23% decrease in unused OR time in 2001 compared to 2000 (35 h 21min vs 46 h 45 min). Therefore, the introduction of an OR information system, with a real-time visual display of ongoing OR activity, resulted in a increased performance of OR activity, with more OR procedures performed despite less excess time and less extra costs.

  7. Level crossings and excess times due to a superposition of uncorrelated exponential pulses

    NASA Astrophysics Data System (ADS)

    Theodorsen, A.; Garcia, O. E.

    2018-01-01

    A well-known stochastic model for intermittent fluctuations in physical systems is investigated. The model is given by a superposition of uncorrelated exponential pulses, and the degree of pulse overlap is interpreted as an intermittency parameter. Expressions for excess time statistics, that is, the rate of level crossings above a given threshold and the average time spent above the threshold, are derived from the joint distribution of the process and its derivative. Limits of both high and low intermittency are investigated and compared to previously known results. In the case of a strongly intermittent process, the distribution of times spent above threshold is obtained analytically. This expression is verified numerically, and the distribution of times above threshold is explored for other intermittency regimes. The numerical simulations compare favorably to known results for the distribution of times above the mean threshold for an Ornstein-Uhlenbeck process. This contribution generalizes the excess time statistics for the stochastic model, which find applications in a wide diversity of natural and technological systems.

  8. Multimedia and children in Turkey.

    PubMed

    Tuncer, A M; Yalçin, S S

    1999-01-01

    Multimedia will be regarded as essential tools for children to create their new world. The effects of television on young children's life have been well studied. Television differs, however, from other media, including the movies, in its pervasive impact on children. Children spend more time watching television than any other activity except sleeping. Overall 31% of children spent at least 4 hours a day watching television during weekday and 71.7% during weekend in Turkey. Television's influence on children is a function of the length of time they spend watching and the cumulative effect of what they see. Television may be a cause as well as a solution for many serious childhood problems. Excessive viewing of television has also been linked to aggressive behavior, violence, childhood obesity. On the other hand, television may act as a socializing agent and as a learning tool if the recommendations of American Academy of Pediatrics is learned by pediatricians, parents and broadcasters. The use of home personal computers in urban residence increased from 3.2% in 1993 to 6.5% by January 1998 in Turkey. Around 20% of computer households reported owing a modem. Internet has been using only for 5 years in Turkey. Nearly 40% of computer households also used CD-ROM equipment. The percentage of schools that have a computer laboratory is only 2.64%. On the other hand, multimedia allows students to move away from a uniform education for everyone to assert individual identity, liberalize education and management. It seems likely that, within the next few years, most of the countries with substantial internet infrastructure will use the internet as the major medium for disseminating information, including information on children. To prepare students for such a world demands that educational systems make the best possible use of all knowledge and technologies currently available.

  9. Excess capacity: markets regulation, and values.

    PubMed Central

    Madden, C W

    1999-01-01

    OBJECTIVE: To examine the conceptual bases for the conflicting views of excess capacity in healthcare markets and their application in the context of today's turbulent environment. STUDY SETTING: The policy and research literature of the past three decades. STUDY DESIGN: The theoretical perspectives of alternative economic schools of thought are used to support different policy positions with regard to excess capacity. Changes in these policy positions over time are linked to changes in the economic and political environment of the period. The social values implied by this history are articulated. DATA COLLECTION: Standard library search procedures are used to identify relevant literature. PRINCIPAL FINDINGS: Alternative policy views of excess capacity in healthcare markets rely on differing theoretical foundations. Changes in the context in which policy decisions are made over time affect the dominant theoretical framework and, therefore, the dominant policy view of excess capacity. CONCLUSIONS: In the 1990s, multiple perspectives of optimal capacity still exist. However, our evolving history suggests a set of persistent values that should guide future policy in this area. PMID:10029502

  10. The short-term and long-term effects of divorce on mortality risk in a large Finnish cohort, 1990-2003.

    PubMed

    Metsä-Simola, Niina; Martikainen, Pekka

    2013-01-01

    This study investigated time patterns of post-divorce excess mortality. Using register-based data, we followed 252,641 married Finns from 1990 until subsequent date of divorce and death until 2003. Among men, excess mortality is highest immediately after divorce, followed by a decline over 8 years. Among women, excess mortality shows little variation over time, and is lower than among men at all durations of divorce. Social and economic factors--largely adjustment for post-divorce factors--explain about half of the excess mortality. This suggests that excess mortality is partly mediated through poor social and economic resources. Mortality attributable to accidental, violent, and alcohol-related causes is pronounced shortly after divorce. It shows a strong pattern of reduction over the next 4 years among divorced men, and is high for only 6 months after divorce among divorced women. These findings emphasize the importance of short-term psychological distress, particularly among men.

  11. Trunk and Hip Muscle Activation Patterns Are Different During Walking in Young Children With and Without Cerebral Palsy

    PubMed Central

    Lee, Samuel C.K.; VanSant, Ann F.; Barbe, Mary F.; Lauer, Richard T.

    2010-01-01

    Background Poor control of postural muscles is a primary impairment in people with cerebral palsy (CP). Objective The purpose of this study was to investigate differences in the timing characteristics of trunk and hip muscle activity during walking in young children with CP compared with children with typical development (TD). Methods Thirty-one children (16 with TD, 15 with CP) with an average of 28.5 months of walking experience participated in this observational study. Electromyographic data were collected from 16 trunk and hip muscles as participants walked at a self-selected pace. A custom-written computer program determined onset and offset of activity. Activation and coactivation data were analyzed for group differences. Results The children with CP had greater total activation and coactivation for all muscles except the external oblique muscle and differences in the timing of activation for all muscles compared with the TD group. The implications of the observed muscle activation patterns are discussed in reference to existing postural control literature. Limitations The potential influence of recording activity from adjacent deep trunk muscles is discussed, as well as the influence of the use of an assistive device by some children with CP. Conclusions Young children with CP demonstrate excessive, nonreciprocal trunk and hip muscle activation during walking compared with children with TD. Future studies should investigate the efficacy of treatments to reduce excessive muscle activity and improve coordination of postural muscles in CP. PMID:20430948

  12. Free energy and entropy of a dipolar liquid by computer simulations

    NASA Astrophysics Data System (ADS)

    Palomar, Ricardo; Sesé, Gemma

    2018-02-01

    Thermodynamic properties for a system composed of dipolar molecules are computed. Free energy is evaluated by means of the thermodynamic integration technique, and it is also estimated by using a perturbation theory approach, in which every molecule is modeled as a hard sphere within a square well, with an electric dipole at its center. The hard sphere diameter, the range and depth of the well, and the dipole moment have been calculated from properties easily obtained in molecular dynamics simulations. Connection between entropy and dynamical properties is explored in the liquid and supercooled states by using instantaneous normal mode calculations. A model is proposed in order to analyze translation and rotation contributions to entropy separately. Both contributions decrease upon cooling, and a logarithmic correlation between excess entropy associated with translation and the corresponding proportion of imaginary frequency modes is encountered. Rosenfeld scaling law between reduced diffusion and excess entropy is tested, and the origin of its failure at low temperatures is investigated.

  13. Bridging the Knowledge Gaps between Richards' Equation and Budyko Equation

    NASA Astrophysics Data System (ADS)

    Wang, D.

    2017-12-01

    The empirical Budyko equation represents the partitioning of mean annual precipitation into evaporation and runoff. Richards' equation, based on Darcy's law, represents the movement of water in unsaturated soils. The linkage between Richards' equation and Budyko equation is presented by invoking the empirical Soil Conservation Service curve number (SCS-CN) model for computing surface runoff at the event-scale. The basis of the SCS-CN method is the proportionality relationship, i.e., the ratio of continuing abstraction to its potential is equal to the ratio of surface runoff to its potential value. The proportionality relationship can be derived from the Richards' equation for computing infiltration excess and saturation excess models at the catchment scale. Meanwhile, the generalized proportionality relationship is demonstrated as the common basis of SCS-CN method, monthly "abcd" model, and Budyko equation. Therefore, the linkage between Darcy's law and the emergent pattern of mean annual water balance at the catchment scale is presented through the proportionality relationship.

  14. Particle trajectory computer program for icing analysis of axisymmetric bodies

    NASA Technical Reports Server (NTRS)

    Frost, Walter; Chang, Ho-Pen; Kimble, Kenneth R.

    1982-01-01

    General aviation aircraft and helicopters exposed to an icing environment can accumulate ice resulting in a sharp increase in drag and reduction of maximum lift causing hazardous flight conditions. NASA Lewis Research Center (LeRC) is conducting a program to examine, with the aid of high-speed computer facilities, how the trajectories of particles contribute to the ice accumulation on airfoils and engine inlets. This study, as part of the NASA/LeRC research program, develops a computer program for the calculation of icing particle trajectories and impingement limits relative to axisymmetric bodies in the leeward-windward symmetry plane. The methodology employed in the current particle trajectory calculation is to integrate the governing equations of particle motion in a flow field computed by the Douglas axisymmetric potential flow program. The three-degrees-of-freedom (horizontal, vertical, and pitch) motion of the particle is considered. The particle is assumed to be acted upon by aerodynamic lift and drag forces, gravitational forces, and for nonspherical particles, aerodynamic moments. The particle momentum equation is integrated to determine the particle trajectory. Derivation of the governing equations and the method of their solution are described in Section 2.0. General features, as well as input/output instructions for the particle trajectory computer program, are described in Section 3.0. The details of the computer program are described in Section 4.0. Examples of the calculation of particle trajectories demonstrating application of the trajectory program to given axisymmetric inlet test cases are presented in Section 5.0. For the examples presented, the particles are treated as spherical water droplets. In Section 6.0, limitations of the program relative to excessive computer time and recommendations in this regard are discussed.

  15. Automated renal histopathology: digital extraction and quantification of renal pathology

    NASA Astrophysics Data System (ADS)

    Sarder, Pinaki; Ginley, Brandon; Tomaszewski, John E.

    2016-03-01

    The branch of pathology concerned with excess blood serum proteins being excreted in the urine pays particular attention to the glomerulus, a small intertwined bunch of capillaries located at the beginning of the nephron. Normal glomeruli allow moderate amount of blood proteins to be filtered; proteinuric glomeruli allow large amount of blood proteins to be filtered. Diagnosis of proteinuric diseases requires time intensive manual examination of the structural compartments of the glomerulus from renal biopsies. Pathological examination includes cellularity of individual compartments, Bowman's and luminal space segmentation, cellular morphology, glomerular volume, capillary morphology, and more. Long examination times may lead to increased diagnosis time and/or lead to reduced precision of the diagnostic process. Automatic quantification holds strong potential to reduce renal diagnostic time. We have developed a computational pipeline capable of automatically segmenting relevant features from renal biopsies. Our method first segments glomerular compartments from renal biopsies by isolating regions with high nuclear density. Gabor texture segmentation is used to accurately define glomerular boundaries. Bowman's and luminal spaces are segmented using morphological operators. Nuclei structures are segmented using color deconvolution, morphological processing, and bottleneck detection. Average computation time of feature extraction for a typical biopsy, comprising of ~12 glomeruli, is ˜69 s using an Intel(R) Core(TM) i7-4790 CPU, and is ~65X faster than manual processing. Using images from rat renal tissue samples, automatic glomerular structural feature estimation was reproducibly demonstrated for 15 biopsy images, which contained 148 individual glomeruli images. The proposed method holds immense potential to enhance information available while making clinical diagnoses.

  16. Timing of Excessive Weight Gain During Pregnancy Modulates Newborn Anthropometry.

    PubMed

    Ruchat, Stephanie-May; Allard, Catherine; Doyon, Myriam; Lacroix, Marilyn; Guillemette, Laetitia; Patenaude, Julie; Battista, Marie-Claude; Ardilouze, Jean-Luc; Perron, Patrice; Bouchard, Luigi; Hivert, Marie-France

    2016-02-01

    Excessive gestational weight gain (GWG) is associated with increased birth weight and neonatal adiposity. However, timing of excessive GWG may have a differential impact on birth outcomes. The objective of this study was to compare the effect of early and mid/late excessive GWG on newborn anthropometry in the context of the Canadian clinical recommendations that are specific for first trimester and for second/third trimesters based on maternal pre-pregnancy BMI. We included 607 glucose-tolerant women in our main analyses, after excluding women who had less than the recommended total GWG. Maternal body weight was measured in early pregnancy, mid-pregnancy, and late pregnancy. Maternal and fetal clinical outcomes were collected, including newborn anthropometry. Women were divided into four groups according to the Canadian guidelines for GWG in the first and in the second/third trimesters: (1) "overall non-excessive" (reference group); (2) "early excessive GWG"; (3) "mid/late excessive GWG"; and (4) "overall excessive GWG." Differences in newborn anthropometry were tested across GWG categories. Women had a mean (±SD) pre-pregnancy BMI of 24.7 ± 5.2 kg/m(2) and total GWG of 15.3 ± 4.4 kg. Women with mid/late excessive GWG gave birth to heavier babies (gestational age-adjusted birth weight z-score 0.33 ± 0.91) compared with women in the reference group (0.00 ± 0.77, P = 0.007), whereas women with early excessive GWG gave birth to babies of similar weight (gestational age-adjusted z-score 0.01 ± 0.86) to the reference group (0.00 ± 0.77, P = 0.84). When we stratified our analyses and investigated women who gained within the recommendations for total GWG, mid/late excessive GWG specifically was associated with greater newborn size, similar to our main analyses. Excessive GWG in mid/late pregnancy in women who did not gain weight excessively in early pregnancy is associated with increased birth size, even in those who gained within the Canadian recommendations for total GWG. Copyright © 2016. Published by Elsevier Inc.

  17. Level II scour analysis for Bridge 35 (RANDTH00650035) on Town Highway 65, crossing the Second Branch White River, Randolph, Vermont

    USGS Publications Warehouse

    Olson, Scott A.

    1996-01-01

    It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

  18. Level II scour analysis for Bridge 2 (BENNCYPARK0002) on Park Street, crossing Furnace Brook, Bennington, Vermont

    USGS Publications Warehouse

    Olson, Scott A.

    1997-01-01

    size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

  19. Level II scour analysis for Bridge 39 (STOWTH00160039) on Town Highway 16, crossing Moss Glen Brook, Stowe, Vermont

    USGS Publications Warehouse

    Ivanoff, Michael A.; Hammond, Robert E.

    1997-01-01

    It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

  20. Level II scour analysis for Bridge 7 (MORRTH00020007) on Town Highway 2 (FAS 239), crossing Ryder Brook, Morristown, Vermont

    USGS Publications Warehouse

    Boehmler, Erick M.; Hammond, Robert E.

    1997-01-01

    It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

  1. Sensing And Force-Reflecting Exoskeleton

    NASA Technical Reports Server (NTRS)

    Eberman, Brian; Fontana, Richard; Marcus, Beth

    1993-01-01

    Sensing and force-reflecting exoskeleton (SAFiRE) provides control signals to robot hand and force feedback from robot hand to human operator. Operator makes robot hand touch objects gently and manipulates them finely without exerting excessive forces. Device attaches to operator's hand; comfortable and lightweight. Includes finger exoskeleton, cable mechanical transmission, two dc servomotors, partial thumb exoskeleton, harness, amplifier box, two computer circuit boards, and software. Transduces motion of index finger and thumb. Video monitor of associated computer displays image corresponding to motion.

  2. Level II scour analysis for Bridge 11 (HINETH00040011) on Town Highway 4, crossing Lewis Creek, Hinesburg, Vermont

    USGS Publications Warehouse

    Ivanoff, Michael A.; Burns, Ronda L.

    1997-01-01

    size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

  3. Level II scour analysis for Bridge 39 (PEACTH00620039) on Town Highway 62, crossing South Peacham Brook, Peacham, Vermont

    USGS Publications Warehouse

    Burns, Ronda L.; Degnan, James R.

    1997-01-01

    It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

  4. Level II scour analysis for Bridge 137 (FERRUS00070137) on U.S. Route 7, crossing Little Otter Creek, Ferrisburg, Vermont

    USGS Publications Warehouse

    Boehmler, Erick M.; Burns, Ronda L.

    1997-01-01

    It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

  5. Level II scour analysis for Bridge 19 (CHARTH00390019) on Town Highway 39, crossing Mad Brook, Charleston, Vermont

    USGS Publications Warehouse

    Boehmler, Erick M.; Hammond, Robert E.

    1997-01-01

    It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

  6. [On the increase in mortality in Italy in 2015: analysis of seasonal mortality in the 32 municipalities included in the Surveillance system of daily mortality].

    PubMed

    Michelozzi, Paola; De' Donato, Francesca; Scortichini, Matteo; De Sario, Manuela; Asta, Federica; Agabiti, Nera; Guerra, Ranieri; de Martino, Annamaria; Davoli, Marina

    2016-01-01

    the Italian National Institute of Statistics (Istat) estimated an increase in mortality in Italy of 11.3% between January and August 2015 compared to the previous year. During summer 2015, an excess in mortality, attributed to heat waves, was observed. to estimate the excess mortality in 2015 using data from the rapid mortality surveillance system (SiSMG) operational in 32 Italian cities. time series models were used to estimate the excess in mortality among the elderly (65+ years) in 2015 by season (winter and summer). Excess mortality was defined as the difference between observed daily and expected (baseline) mortality for the five previous years (2009- 2013); seasonal mortality in 2015 was compared with mortality observed in 2012, 2013, and 2014. An analysis by cause of death (cardiovascular and respiratory), gender, and age group was carried out in Rome. data confirm an overall estimated excess in mortality of +11% in 2015. Seasonal analysis shows a greater excess in winter (+13%) compared to the summer period (+10%). The excess in winter deaths seems to be attributable to the peak in influenza rather than to low temperatures. Summer excess mortality was attributed to the heat waves of July and August 2015. The lower mortality registered in Italy during summer 2014 (-5.9%) may have contributed to the greater excess registered in 2015. In Rome, cause-specific analysis showed a higher excess among the very old (85+ years) mainly for cardiovascular and respiratory causes in winter. In summer, the excess was observed among both the elderly and in the adult population (35-64 years). results suggest the need for a more timely use of mortality data to evaluate the impact of different risk factors. Public health measures targeted to susceptible subgroups should be enhanced (e.g., Heat Prevention Plans, flu vaccination campaigns).

  7. Spin Rate Distribution of Small Asteroids Shaped by YORP Effect

    NASA Astrophysics Data System (ADS)

    Pravec, Petr

    2008-09-01

    We studied a distribution of spin rates of main belt/Mars crossing (MB/MC) asteroids with diameters 3-15 km using data obtained within the Photometric Survey of Asynchronous Binary Asteroids (Pravec et al. 2008). We found that the spin distribution of the small asteroids is uniform in the range from f = 1 to 9.5 d-1, and there is an excess of slow rotators with f < 1 d-1. The observed distribution appears to be controlled by the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect. The magnitude of the excess of slow rotators is related to the residence time of slowed down asteroids in the excess and the rate of spin rate change outside the excess. We estimated a median YORP spin rate change of 0.022 d-1/Myr for asteroids in our sample (i.e., a median time in which the spin rate changes by 1 d-1 is 45 Myr), thus the residence time of slowed down asteroids in the excess is 110 Myr. The spin rate distribution of near-Earth asteroids (NEAs) with sizes in the range 0.2-3 km ( 5-times smaller in median diameter than the MB/MC asteroids sample) shows a similar excess of slow rotators, but there is also a concentration of NEAs at fast spin rates with f = 9-10 d-1. The concentration at fast spin rates is correlated with a narrower distribution of spin rates of primaries of binary systems among NEAs; the difference may be due to the apparently more evolved population of binaries among MB/MC asteroids. Reference: Pravec, P., and 30 colleagues, 2008. Spin rate distribution of small asteroids. Icarus, in press. DOI: http://dx.doi.org/10.1016/j.icarus.2008.05.012

  8. 26 CFR 1.668(b)-1A - Tax on distribution.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...)-1A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Treatment of Excess Distributions of Trusts Applicable to Taxable Years Beginning... the section 666 amounts in the beneficiary's gross income and the tax for such year computed without...

  9. 7 CFR 3203.7 - Title.

    Code of Federal Regulations, 2010 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Title. 3203.7 Section 3203.7 Agriculture Regulations of the Department of Agriculture (Continued) OFFICE OF PROCUREMENT AND PROPERTY MANAGEMENT... PURSUANT TO SECTION 14220 OF THE 2008 FARM BILL § 3203.7 Title. Title of ownership to excess computers or...

  10. Effects of parents' employment status on changes in body mass index and percent body fat in adolescent girls.

    PubMed

    Lee, Sunmin; Young, Deborah Rohm; Pratt, Charlotte A; Jobe, Jared B; Chae, Soo Eun; McMurray, Robert G; Johnson, Carolyn C; Going, Scott B; Elder, John P; Stevens, June

    2012-12-01

    Parents' employment status is frequently cited as a possible predictor of child weight status. Despite the importance of the topic, only a few studies have been conducted. No longitudinal studies have been conducted in the United States. A cohort of 1201 girls from the Trial of Activity for Adolescent Girls was used. Height, weight, and percent body fat (PBF) were measured at the 6th and 8th grades. Parents' employment status (measured at 6th grade) was categorized into working full time (reference), part time, unemployed, working or staying at home, and don't know. Mixed-model regression was used to reflect the hierarchical design of our study and adjusted for age, race, parents' education level, free or reduced-price school lunch status, and living arrangement. Girls whose mothers worked part time or stayed at home had a decreased risk of excess weight gain [relative risk (RR) = 0.94, 95% confidence interval (CI) 0.88, 1.00; RR = 0.89, 95% CI 0.79, 1.00, respectively] compared to girls whose mothers worked full time. Girls whose fathers were unemployed had a moderately increased risk of excess weight gain (RR = 1.13, 95% CI 1.00, 1.26) compared to girls whose fathers worked full time. Having an unemployed mother or part-time or stay-at-home father was not associated with excess weight gain. Parents' employment status was not associated with excess PBF gain. Our findings suggest that the availability of the mother has a greater influence on the weight of the daughter than the availability of the father. There is a need for a better understanding of how parents' employment status influences excess weight gain in adolescent girls.

  11. Effects of Parents' Employment Status on Changes in Body Mass Index and Percent Body Fat in Adolescent Girls

    PubMed Central

    Young, Deborah Rohm; Pratt, Charlotte A.; Jobe, Jared B.; Chae, Soo Eun; McMurray, Robert G.; Johnson, Carolyn C.; Going, Scott B.; Elder, John P.; Stevens, June

    2012-01-01

    Abstract Background Parents' employment status is frequently cited as a possible predictor of child weight status. Despite the importance of the topic, only a few studies have been conducted. No longitudinal studies have been conducted in the United States. Methods A cohort of 1201 girls from the Trial of Activity for Adolescent Girls was used. Height, weight, and percent body fat (PBF) were measured at the 6th and 8th grades. Parents' employment status (measured at 6th grade) was categorized into working full time (reference), part time, unemployed, working or staying at home, and don't know. Mixed-model regression was used to reflect the hierarchical design of our study and adjusted for age, race, parents' education level, free or reduced-price school lunch status, and living arrangement. Results Girls whose mothers worked part time or stayed at home had a decreased risk of excess weight gain [relative risk (RR)=0.94, 95% confidence interval (CI) 0.88, 1.00; RR=0.89, 95% CI 0.79, 1.00, respectively] compared to girls whose mothers worked full time. Girls whose fathers were unemployed had a moderately increased risk of excess weight gain (RR=1.13, 95% CI 1.00, 1.26) compared to girls whose fathers worked full time. Having an unemployed mother or part-time or stay-at-home father was not associated with excess weight gain. Parents' employment status was not associated with excess PBF gain. Conclusions Our findings suggest that the availability of the mother has a greater influence on the weight of the daughter than the availability of the father. There is a need for a better understanding of how parents' employment status influences excess weight gain in adolescent girls. PMID:23181918

  12. Computer games: a double-edged sword?

    PubMed

    Sun, De-Lin; Ma, Ning; Bao, Min; Chen, Xang-Chuan; Zhang, Da-Ren

    2008-10-01

    Excessive computer game playing (ECGP) has already become a serious social problem. However, limited data from experimental lab studies are available about the negative consequences of ECGP on players' cognitive characteristics. In the present study, we compared three groups of participants (current ECGP participants, previous ECGP participants, and control participants) on a Multiple Object Tracking (MOT) task. The previous ECGP participants performed significantly better than the control participants, which suggested a facilitation effect of computer games on visuospatial abilities. Moreover, the current ECGP participants performed significantly worse than the previous ECGP participants. This more important finding indicates that ECGP may be related to cognitive deficits. Implications of this study are discussed.

  13. A computational study of the TiO2 molecule

    NASA Technical Reports Server (NTRS)

    Ramana, M. V.; Phillips, D. H.

    1988-01-01

    A computational investigation of the ground 1A1 and lowest energy B2 states of the titanium dioxide molecule has been carried out. The treatment utilized SCF calculations in an extended basis followed by a CI treatment for each geometry. The ground state geometry agrees well with experiment, while the agreement between the computed vibrational frequency nu1 and the experimental value for a matrix isolated TiO2 is less satisfactory. Population analysis for the ground state indicates less than one excess electron on each oxygen atom. The first excited state has a linear geometry and the singlet and triplet are essentially degenerate.

  14. TRIGRS - A Fortran Program for Transient Rainfall Infiltration and Grid-Based Regional Slope-Stability Analysis, Version 2.0

    USGS Publications Warehouse

    Baum, Rex L.; Savage, William Z.; Godt, Jonathan W.

    2008-01-01

    The Transient Rainfall Infiltration and Grid-Based Regional Slope-Stability Model (TRIGRS) is a Fortran program designed for modeling the timing and distribution of shallow, rainfall-induced landslides. The program computes transient pore-pressure changes, and attendant changes in the factor of safety, due to rainfall infiltration. The program models rainfall infiltration, resulting from storms that have durations ranging from hours to a few days, using analytical solutions for partial differential equations that represent one-dimensional, vertical flow in isotropic, homogeneous materials for either saturated or unsaturated conditions. Use of step-function series allows the program to represent variable rainfall input, and a simple runoff routing model allows the user to divert excess water from impervious areas onto more permeable downslope areas. The TRIGRS program uses a simple infinite-slope model to compute factor of safety on a cell-by-cell basis. An approximate formula for effective stress in unsaturated materials aids computation of the factor of safety in unsaturated soils. Horizontal heterogeneity is accounted for by allowing material properties, rainfall, and other input values to vary from cell to cell. This command-line program is used in conjunction with geographic information system (GIS) software to prepare input grids and visualize model results.

  15. A program for calculation of intrapulmonary shunts, blood-gas and acid-base values with a programmable calculator.

    PubMed

    Ruiz, B C; Tucker, W K; Kirby, R R

    1975-01-01

    With a desk-top, programmable calculator, it is now possible to do complex, previously time-consuming computations in the blood-gas laboratory. The authors have developed a program with the necessary algorithms for temperature correction of blood gases and calculation of acid-base variables and intrapulmonary shunt. It was necessary to develop formulas for the Po2 temperature-correction coefficient, the oxyhemoglobin-dissociation curve for adults (withe necessary adjustments for fetal blood), and changes in water vapor pressure due to variation in body temperature. Using this program in conjuction with a Monroe 1860-21 statistical programmable calculator, it is possible to temperature-correct pH,Pco2, and Po2. The machine will compute alveolar-arterial oxygen tension gradient, oxygen saturation (So2), oxygen content (Co2), actual HCO minus 3 and a modified base excess. If arterial blood and mixed venous blood are obtained, the calculator will print out intrapulmonary shunt data (Qs/Qt) and arteriovenous oxygen differences (a minus vDo2). There also is a formula to compute P50 if pH,Pco2,Po2, and measured So2 from two samples of tonometered blood (one above 50 per cent and one below 50 per cent saturation) are put into the calculator.

  16. A Domain-Decomposed Multilevel Method for Adaptively Refined Cartesian Grids with Embedded Boundaries

    NASA Technical Reports Server (NTRS)

    Aftosmis, M. J.; Berger, M. J.; Adomavicius, G.

    2000-01-01

    Preliminary verification and validation of an efficient Euler solver for adaptively refined Cartesian meshes with embedded boundaries is presented. The parallel, multilevel method makes use of a new on-the-fly parallel domain decomposition strategy based upon the use of space-filling curves, and automatically generates a sequence of coarse meshes for processing by the multigrid smoother. The coarse mesh generation algorithm produces grids which completely cover the computational domain at every level in the mesh hierarchy. A series of examples on realistically complex three-dimensional configurations demonstrate that this new coarsening algorithm reliably achieves mesh coarsening ratios in excess of 7 on adaptively refined meshes. Numerical investigations of the scheme's local truncation error demonstrate an achieved order of accuracy between 1.82 and 1.88. Convergence results for the multigrid scheme are presented for both subsonic and transonic test cases and demonstrate W-cycle multigrid convergence rates between 0.84 and 0.94. Preliminary parallel scalability tests on both simple wing and complex complete aircraft geometries shows a computational speedup of 52 on 64 processors using the run-time mesh partitioner.

  17. Very Large Scale Optimization

    NASA Technical Reports Server (NTRS)

    Vanderplaats, Garrett; Townsend, James C. (Technical Monitor)

    2002-01-01

    The purpose of this research under the NASA Small Business Innovative Research program was to develop algorithms and associated software to solve very large nonlinear, constrained optimization tasks. Key issues included efficiency, reliability, memory, and gradient calculation requirements. This report describes the general optimization problem, ten candidate methods, and detailed evaluations of four candidates. The algorithm chosen for final development is a modern recreation of a 1960s external penalty function method that uses very limited computer memory and computational time. Although of lower efficiency, the new method can solve problems orders of magnitude larger than current methods. The resulting BIGDOT software has been demonstrated on problems with 50,000 variables and about 50,000 active constraints. For unconstrained optimization, it has solved a problem in excess of 135,000 variables. The method includes a technique for solving discrete variable problems that finds a "good" design, although a theoretical optimum cannot be guaranteed. It is very scalable in that the number of function and gradient evaluations does not change significantly with increased problem size. Test cases are provided to demonstrate the efficiency and reliability of the methods and software.

  18. Analysis of turbulent free jet hydrogen-air diffusion flames with finite chemical reaction rates

    NASA Technical Reports Server (NTRS)

    Sislian, J. P.

    1978-01-01

    The nonequilibrium flow field resulting from the turbulent mixing and combustion of a supersonic axisymmetric hydrogen jet in a supersonic parallel coflowing air stream is analyzed. Effective turbulent transport properties are determined using the (K-epsilon) model. The finite-rate chemistry model considers eight reactions between six chemical species, H, O, H2O, OH, O2, and H2. The governing set of nonlinear partial differential equations is solved by an implicit finite-difference procedure. Radial distributions are obtained at two downstream locations of variables such as turbulent kinetic energy, turbulent dissipation rate, turbulent scale length, and viscosity. The results show that these variables attain peak values at the axis of symmetry. Computed distributions of velocity, temperature, and mass fraction are also given. A direct analytical approach to account for the effect of species concentration fluctuations on the mean production rate of species (the phenomenon of unmixedness) is also presented. However, the use of the method does not seem justified in view of the excessive computer time required to solve the resulting system of equations.

  19. Numerical simulation of low gravity draining. [computerized simulation of liquid sloshing in cylindrical tanks, and boundary value problems

    NASA Technical Reports Server (NTRS)

    Bizzell, G. D.; Crane, G. E.

    1976-01-01

    A boundary value problem was solved numerically for a liquid that is assumed to be inviscid and incompressible, having a motion that is irrotational and axisymmetric, and having a constant (5 degrees) solid-liquid contact angle. The avoidance of excessive mesh distortion, encountered with strictly Lagrangian or Eulerian kinematics, was achieved by introducing an auxiliary kinematic velocity field along the free surface in order to vary the trajectories used in integrating the ordinary differential equations simulating the moving boundary. The computation of the velocity potential was based upon a nonuniform triangular mesh which was automatically revised to varying depths to accommodate the motion of the free surface. These methods permitted calculation of draining induced axisymmetric slosh through the many (or fractional) finite amplitude oscillations that can occur depending upon the balance of draining, gravitational, and surface tension forces. Velocity fields, evolution of the free surface with time, and liquid residual volumes were computed for three and one half decades of Weber number and for two Bond numbers, tank fill levels, and drain radii. Comparisons with experimental data are very satisfactory.

  20. Autoblocker: a system for detecting and blocking of network scanning based on analysis of netflow data

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bobyshev, A.; Lamore, D.; Demar, P.

    2004-12-01

    In a large campus network, such at Fermilab, with tens of thousands of nodes, scanning initiated from either outside of or within the campus network raises security concerns. This scanning may have very serious impact on network performance, and even disrupt normal operation of many services. In this paper we introduce a system for detecting and automatic blocking excessive traffic of different kinds of scanning, DoS attacks, virus infected computers. The system, called AutoBlocker, is a distributed computing system based on quasi-real time analysis of network flow data collected from the border router and core switches. AutoBlocker also has anmore » interface to accept alerts from IDS systems (e.g. BRO, SNORT) that are based on other technologies. The system has multiple configurable alert levels for the detection of anomalous behavior and configurable trigger criteria for automated blocking of scans at the core or border routers. It has been in use at Fermilab for about 2 years, and has become a very valuable tool to curtail scan activity within the Fermilab campus network.« less

  1. A Numerical Model for Two-Plasmon-Decay Hot-Electron Production and Mitigation in Direct-Drive Implosions

    NASA Astrophysics Data System (ADS)

    Myatt, J. F.; Shaw, J. G.; Solodov, A. A.; Maximov, A. V.; Short, R. W.; Seka, W.; Follett, R. K.; Edgell, D. H.; Froula, D. H.; Goncharov, V. N.

    2015-11-01

    Hot-electron preheat, caused by laser-plasma instabilities, can impair the performance of inertial confinement fusion implosions. It is therefore imperative to understand processes that can generate hot electrons and to design mitigation strategies should preheat be found to be excessive at the ignition scale (laser-plasma interactions do not follow hydrodynamic scaling). For this purpose, a new 3-D model [laser-plasma simulation environment (LPSE)] has been constructed that computes hot-electron generation in direct-drive plasmas based on the assumption that two-plasmon decay is the dominant, hot-electron-producing instability. It uses an established model of TPD-driven turbulence together with a new GPU based hybrid particle method of hot-electron production. The time-dependent hot-electron power, total energy, and energy spectrum are computed and compared with data from recent OMEGA implosion experiments that have sought to mitigate TPD by the use of multilayered (mid- Z) ablators. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  2. Association between screen time and snack consumption in children and adolescents: The CASPIAN-IV study.

    PubMed

    Kelishadi, Roya; Mozafarian, Nafiseh; Qorbani, Mostafa; Maracy, Mohammad Reza; Motlagh, Mohammad Esmaeil; Safiri, Saeid; Ardalan, Gelayol; Asayesh, Hamid; Rezaei, Fatemeh; Heshmat, Ramin

    2017-02-01

    The relationship between screen time (ST) and the frequency of snack consumption in a national sample of Iranian children and adolescents was assessed. The present nationwide survey was conducted on 14,880 school students living in urban and rural areas of 30 provinces in Iran. Trained healthcare providers conducted the physical examination and completed the questionnaire of the World Health Organization - Global School-Based Student Health Survey (WHO-GSHS). The association between ST (total time spent watching TV and using a computer in leisure time) and the frequency of snack consumption was determined using ordinal logistic regression analysis. The subjects were 13,486 students out of the 14,880 invited including 50.8% boys. The mean (SD) age of participants was 12.47 (3.36) years. In multivariate models, for students who had prolonged ST (more than 4 h/day), the odds of daily consumption of sweets (odds ratio, OR 1.25; 95% CI 1.14-1.4), salty snacks (OR 1.6; 95% CI 1.5-1.76), soft drinks (OR 1.52; 95% CI 1.4-1.7), canned fruit juice (OR 1.3; 95% CI 1.2-1.4), and fast food (OR 1.53; 95% CI 1.4-1.7) were higher compared to those with low ST. Furthermore, the odds of daily consumption of milk in students who had prolonged ST (more than 4 h/day) were lower compared to those with low ST (OR 0.9; 95% CI 0.8-0.99). Prolonged time spent watching TV and using a computer during leisure time might be associated with unhealthy dietary habits. Moreover, inactivity induced by prolonged ST may also lead to unhealthy dietary habits and in turn excess weight in children and adolescents.

  3. Thermophysical properties of N, N-dimethylacetamide mixtures with n-butanol

    NASA Astrophysics Data System (ADS)

    Maharolkar, Aruna P.; Murugkar, A. G.; Khirade, P. W.; Mehrotra, S. C.

    2017-09-01

    The refraction, dielectric, viscosity, density, data of the binary mixtures of N, N-dimethylacetamide (DMA) with n-butanol at 308.15 and 313.15 K. The measured parameters used to obtain derived properties like Bruggeman factor, molar refraction and excess static dielectric constant, excess inverse relaxation time, excess molar volume and excess viscosity, excess molar refraction. The variation in magnitude with composition and temperature of these quantities has been used to discuss the type, strength and nature of binary interactions. Results confirm that there are strong hydrogen-bond interactions between unlike molecules of DMA+ n-butanol mixtures and that 1: 1 complexes are formed and strength of intermolecular interaction increases with temperature.

  4. Investigations on transparent liquid-miscibility gap systems

    NASA Technical Reports Server (NTRS)

    Lacy, L. L.; Nishioka, G.; Ross, S.

    1979-01-01

    Sedimentation and phase separation is a well known occurrence in monotectic or miscibility gap alloys. Previous investigations indicate that it may be possible to prepare such alloys in a low-gravity space environment but recent experiments indicate that there may be nongravity dependent phase separation processes which can hinder the formation of such alloys. Such phase separation processes are studied using transparent liquid systems and holography. By reconstructing holograms into a commercial-particle-analysis system, real time computer analysis can be performed on emulsions with diameters in the range of 5 micrometers or greater. Thus dynamic effects associated with particle migration and coalescence can be studied. Characterization studies on two selected immiscible systems including an accurate determination of phase diagrams, surface and interfacial tension measurements, surface excess and wetting behavior near critical solution temperatures completed.

  5. Excess morbidity and mortality in patients with craniopharyngioma: a hospital-based retrospective cohort study.

    PubMed

    Wijnen, Mark; Olsson, Daniel S; van den Heuvel-Eibrink, Marry M; Hammarstrand, Casper; Janssen, Joseph A M J L; van der Lely, Aart J; Johannsson, Gudmundur; Neggers, Sebastian J C M M

    2018-01-01

    Most studies in patients with craniopharyngioma did not investigate morbidity and mortality relative to the general population nor evaluated risk factors for excess morbidity and mortality. Therefore, the objective of this study was to examine excess morbidity and mortality, as well as their determinants in patients with craniopharyngioma. Hospital-based retrospective cohort study conducted between 1987 and 2014. We included 144 Dutch and 80 Swedish patients with craniopharyngioma identified by a computer-based search in the medical records (105 females (47%), 112 patients with childhood-onset craniopharyngioma (50%), 3153 person-years of follow-up). Excess morbidity and mortality were analysed using standardized incidence and mortality ratios (SIRs and SMRs). Risk factors were evaluated univariably by comparing SIRs and SMRs between non-overlapping subgroups. Patients with craniopharyngioma experienced excess morbidity due to type 2 diabetes mellitus (T2DM) (SIR: 4.4, 95% confidence interval (CI): 2.8-6.8) and cerebral infarction (SIR: 4.9, 95% CI: 3.1-8.0) compared to the general population. Risks for malignant neoplasms, myocardial infarctions and fractures were not increased. Patients with craniopharyngioma also had excessive total mortality (SMR: 2.7, 95% CI: 2.0-3.8), and mortality due to circulatory (SMR: 2.3, 95% CI: 1.1-4.5) and respiratory (SMR: 6.0, 95% CI: 2.5-14.5) diseases. Female sex, childhood-onset craniopharyngioma, hydrocephalus and tumour recurrence were identified as risk factors for excess T2DM, cerebral infarction and total mortality. Patients with craniopharyngioma are at an increased risk for T2DM, cerebral infarction, total mortality and mortality due to circulatory and respiratory diseases. Female sex, childhood-onset craniopharyngioma, hydrocephalus and tumour recurrence are important risk factors. © 2018 European Society of Endocrinology.

  6. Control of Bethlehem's coke-oven battery A at Sparrow Point

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Michel, A.

    1984-02-01

    A new 6 m 80-oven compound-fired coke battery capable of producing in excess of 850,000 ton/year began production at Sparrow Point, Maryland, in 1982. The electrical, fuel distribution and control systems are described, together with the computer process control and monitoring systems.

  7. 26 CFR 1.1251-2 - Excess deductions account.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., and livestock used in the trade or business of farming which is held for draft, breeding, dairy, or... $13,000 (b) Gain from disposition of breeding herd to which section 1251(c)(1) applies (computed... include all expenditures paid or incurred for producing the animal, such as for stud, breeding, and...

  8. 26 CFR 1.668(b)-1A - Tax on distribution.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...)-1A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Treatment of Excess Distributions of Trusts Applicable to Taxable Years... inclusion of the section 666 amounts in the beneficiary's gross income and the tax for such year computed...

  9. The Information Society: Byting the Hand that Feeds You.

    ERIC Educational Resources Information Center

    Bernstein, Harriet T.

    1983-01-01

    This position paper denounces what the author considers to be an increasing and excessive reliance on computers and technological advancements generally as panaceas for educational and social problems whose real resolution demands the skills of "citizens with a basic liberal arts education" rather than those of technocrats. (JBM)

  10. A direct Arbitrary-Lagrangian-Eulerian ADER-WENO finite volume scheme on unstructured tetrahedral meshes for conservative and non-conservative hyperbolic systems in 3D

    NASA Astrophysics Data System (ADS)

    Boscheri, Walter; Dumbser, Michael

    2014-10-01

    In this paper we present a new family of high order accurate Arbitrary-Lagrangian-Eulerian (ALE) one-step ADER-WENO finite volume schemes for the solution of nonlinear systems of conservative and non-conservative hyperbolic partial differential equations with stiff source terms on moving tetrahedral meshes in three space dimensions. A WENO reconstruction technique is used to achieve high order of accuracy in space, while an element-local space-time Discontinuous Galerkin finite element predictor on moving curved meshes is used to obtain a high order accurate one-step time discretization. Within the space-time predictor the physical element is mapped onto a reference element using a high order isoparametric approach, where the space-time basis and test functions are given by the Lagrange interpolation polynomials passing through a predefined set of space-time nodes. Since our algorithm is cell-centered, the final mesh motion is computed by using a suitable node solver algorithm. A rezoning step as well as a flattener strategy are used in some of the test problems to avoid mesh tangling or excessive element deformations that may occur when the computation involves strong shocks or shear waves. The ALE algorithm presented in this article belongs to the so-called direct ALE methods because the final Lagrangian finite volume scheme is based directly on a space-time conservation formulation of the governing PDE system, with the rezoned geometry taken already into account during the computation of the fluxes. We apply our new high order unstructured ALE schemes to the 3D Euler equations of compressible gas dynamics, for which a set of classical numerical test problems has been solved and for which convergence rates up to sixth order of accuracy in space and time have been obtained. We furthermore consider the equations of classical ideal magnetohydrodynamics (MHD) as well as the non-conservative seven-equation Baer-Nunziato model of compressible multi-phase flows with stiff relaxation source terms.

  11. Advances in visual representation of molecular potentials.

    PubMed

    Du, Qi-Shi; Huang, Ri-Bo; Chou, Kuo-Chen

    2010-06-01

    The recent advances in visual representations of molecular properties in 3D space are summarized, and their applications in molecular modeling study and rational drug design are introduced. The visual representation methods provide us with detailed insights into protein-ligand interactions, and hence can play a major role in elucidating the structure or reactivity of a biomolecular system. Three newly developed computation and visualization methods for studying the physical and chemical properties of molecules are introduced, including their electrostatic potential, lipophilicity potential and excess chemical potential. The newest application examples of visual representations in structure-based rational drug are presented. The 3D electrostatic potentials, calculated using the empirical method (EM-ESP), in which the classical Coulomb equation and traditional atomic partial changes are discarded, are highly consistent with the results by the higher level quantum chemical method. The 3D lipophilicity potentials, computed by the heuristic molecular lipophilicity potential method based on the principles of quantum mechanics and statistical mechanics, are more accurate and reliable than those by using the traditional empirical methods. The 3D excess chemical potentials, derived by the reference interaction site model-hypernetted chain theory, provide a new tool for computational chemistry and molecular modeling. For structure-based drug design, the visual representations of molecular properties will play a significant role in practical applications. It is anticipated that the new advances in computational chemistry will stimulate the development of molecular modeling methods, further enriching the visual representation techniques for rational drug design, as well as other relevant fields in life science.

  12. Screenieboppers and extreme screenies: the place of screen time in the time budgets of 10-13 year-old Australian children.

    PubMed

    Olds, Tim; Ridley, Kate; Dollman, Jim

    2006-04-01

    Excessive 'screen time' has been associated with a range of psychosocial disturbances and increasing pediatric obesity. This study describes the magnitude, distribution, composition and time-distribution of children's screen use; examines correlates of screen use; and characterises 'extreme' screen users (top quartile). 1,039 South Australian children aged 10-13 years old completed a multimedia 24-hour activity recall diary on 2-4 occasions in 2002, including at least one school day and one non-school day. The median screen time was 229 minutes.d(-1). This was higher in boys (264 vs. 196 minutes; p<0.001) and on non-school days (260 vs. 190 minutes; p<0.001), increased with age (p=0.003), and decreased with socio-economic status (SES; p=0.003). Television consumed 73% of all screen time, video games 19%, non-game computer use 6%, and cinema 2%. The top quartile of screen users were more likely to be boys (OR=3.8), have low physical activity (OR=4.3), spend >25% of screen time playing video games (OR=1.8), sleep less, and be of lower SES. Interventions to reduce screen time should target inactive, low-SES boys, encourage earlier bedtimes, and limit video game use.

  13. Multiresolution persistent homology for excessively large biomolecular datasets

    NASA Astrophysics Data System (ADS)

    Xia, Kelin; Zhao, Zhixiong; Wei, Guo-Wei

    2015-10-01

    Although persistent homology has emerged as a promising tool for the topological simplification of complex data, it is computationally intractable for large datasets. We introduce multiresolution persistent homology to handle excessively large datasets. We match the resolution with the scale of interest so as to represent large scale datasets with appropriate resolution. We utilize flexibility-rigidity index to access the topological connectivity of the data set and define a rigidity density for the filtration analysis. By appropriately tuning the resolution of the rigidity density, we are able to focus the topological lens on the scale of interest. The proposed multiresolution topological analysis is validated by a hexagonal fractal image which has three distinct scales. We further demonstrate the proposed method for extracting topological fingerprints from DNA molecules. In particular, the topological persistence of a virus capsid with 273 780 atoms is successfully analyzed which would otherwise be inaccessible to the normal point cloud method and unreliable by using coarse-grained multiscale persistent homology. The proposed method has also been successfully applied to the protein domain classification, which is the first time that persistent homology is used for practical protein domain analysis, to our knowledge. The proposed multiresolution topological method has potential applications in arbitrary data sets, such as social networks, biological networks, and graphs.

  14. Photophysics of sunscreen molecules in the gas phase: a stepwise approach towards understanding and developing next-generation sunscreens

    PubMed Central

    Rodrigues, Natércia D. N.; Staniforth, Michael

    2016-01-01

    The relationship between exposure to ultraviolet (UV) radiation and skin cancer urges the need for extra photoprotection, which is presently provided by widespread commercially available sunscreen lotions. Apart from having a large absorption cross section in the UVA and UVB regions of the electromagnetic spectrum, the chemical absorbers in these photoprotective products should also be able to dissipate the excess energy in a safe way, i.e. without releasing photoproducts or inducing any further, harmful, photochemistry. While sunscreens are tested for both their photoprotective capability and dermatological compatibility, phenomena occurring at the molecular level upon absorption of UV radiation are largely overlooked. To date, there is only a limited amount of information regarding the photochemistry and photophysics of these sunscreen molecules. However, a thorough understanding of the intrinsic mechanisms by which popular sunscreen molecular constituents dissipate excess energy has the potential to aid in the design of more efficient, safer sunscreens. In this review, we explore the potential of using gas-phase frequency- and time-resolved spectroscopies in an effort to better understand the photoinduced excited-state dynamics, or photodynamics, of sunscreen molecules. Complementary computational studies are also briefly discussed. Finally, the future outlook of expanding these gas-phase studies into the solution phase is considered. PMID:27956888

  15. Photophysics of sunscreen molecules in the gas phase: a stepwise approach towards understanding and developing next-generation sunscreens

    NASA Astrophysics Data System (ADS)

    Rodrigues, Natércia D. N.; Staniforth, Michael; Stavros, Vasilios G.

    2016-11-01

    The relationship between exposure to ultraviolet (UV) radiation and skin cancer urges the need for extra photoprotection, which is presently provided by widespread commercially available sunscreen lotions. Apart from having a large absorption cross section in the UVA and UVB regions of the electromagnetic spectrum, the chemical absorbers in these photoprotective products should also be able to dissipate the excess energy in a safe way, i.e. without releasing photoproducts or inducing any further, harmful, photochemistry. While sunscreens are tested for both their photoprotective capability and dermatological compatibility, phenomena occurring at the molecular level upon absorption of UV radiation are largely overlooked. To date, there is only a limited amount of information regarding the photochemistry and photophysics of these sunscreen molecules. However, a thorough understanding of the intrinsic mechanisms by which popular sunscreen molecular constituents dissipate excess energy has the potential to aid in the design of more efficient, safer sunscreens. In this review, we explore the potential of using gas-phase frequency- and time-resolved spectroscopies in an effort to better understand the photoinduced excited-state dynamics, or photodynamics, of sunscreen molecules. Complementary computational studies are also briefly discussed. Finally, the future outlook of expanding these gas-phase studies into the solution phase is considered.

  16. Mixing the Green-Ampt model and Curve Number method as an empirical tool for rainfall excess estimation in small ungauged catchments.

    NASA Astrophysics Data System (ADS)

    Grimaldi, S.; Petroselli, A.; Romano, N.

    2012-04-01

    The Soil Conservation Service - Curve Number (SCS-CN) method is a popular rainfall-runoff model that is widely used to estimate direct runoff from small and ungauged basins. The SCS-CN is a simple and valuable approach to estimate the total stream-flow volume generated by a storm rainfall, but it was developed to be used with daily rainfall data. To overcome this drawback, we propose to include the Green-Ampt (GA) infiltration model into a mixed procedure, which is referred to as CN4GA (Curve Number for Green-Ampt), aiming to distribute in time the information provided by the SCS-CN method so as to provide estimation of sub-daily incremental rainfall excess. For a given storm, the computed SCS-CN total net rainfall amount is used to calibrate the soil hydraulic conductivity parameter of the Green-Ampt model. The proposed procedure was evaluated by analyzing 100 rainfall-runoff events observed in four small catchments of varying size. CN4GA appears an encouraging tool for predicting the net rainfall peak and duration values and has shown, at least for the test cases considered in this study, a better agreement with observed hydrographs than that of the classic SCS-CN method.

  17. Projected cancer risks potentially related to past, current, and future practices in paediatric CT in the United Kingdom, 1990-2020.

    PubMed

    Journy, Neige M Y; Lee, Choonsik; Harbron, Richard W; McHugh, Kieran; Pearce, Mark S; Berrington de González, Amy

    2017-01-03

    To project risks of developing cancer and the number of cases potentially induced by past, current, and future computed tomography (CT) scans performed in the United Kingdom in individuals aged <20 years. Organ doses were estimated from surveys of individual scan parameters and CT protocols used in the United Kingdom. Frequencies of scans were estimated from the NHS Diagnostic Imaging Dataset. Excess lifetime risks (ELRs) of radiation-related cancer were calculated as cumulative lifetime risks, accounting for survival probabilities, using the RadRAT risk assessment tool. In 2000-2008, ELRs ranged from 0.3 to 1 per 1000 head scans and 1 to 5 per 1000 non-head scans. ELRs per scan were reduced by 50-70% in 2000-2008 compared with 1990-1995, subsequent to dose reduction over time. The 130 750 scans performed in 2015 in the United Kingdom were projected to induce 64 (90% uncertainty interval (UI): 38-113) future cancers. Current practices would lead to about 300 (90% UI: 230-680) future cancers induced by scans performed in 2016-2020. Absolute excess risks from single exposures would be low compared with background risks, but even small increases in annual CT rates over the next years would substantially increase the number of potential subsequent cancers.

  18. French consensus. Idiopathic hypersomnia: Investigations and follow-up.

    PubMed

    Leu-Semenescu, S; Quera-Salva, M-A; Dauvilliers, Y

    Idiopathic hypersomnia is a rare, central hypersomnia, recently identified and to date of unknown physiopathology. It is characterised by a more or less permanent, excessive daytime sleepiness, associated with long and unrefreshing naps. Night-time sleep is of good quality, excessive in quantity, associated with sleep inertia in the subtype previously described as "with long sleep time". Diagnosis of idiopathic hypersomnia is complex due to the absence of a quantifiable biomarker, the heterogeneous symptoms, which overlap with the clinical picture of type 2 narcolepsy, and its variable evolution over time. Detailed evaluation enables other frequent causes of somnolence, such as depression or sleep deprivation, to be eliminated. Polysomnography and multiple sleep latency tests (MSLT) are essential to rule out other sleep pathologies and to objectify excessive daytime sleepiness. Sometimes the MSLT do not show excessive sleepiness, hence a continued sleep recording of at least 24hours is necessary to show prolonged sleep (>11h/24h). In this article, we propose recommendations for the work-up to be carried out during diagnosis and follow-up for patients suffering from idiopathic hypersomnia. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  19. Slicing Method for curved façade and window extraction from point clouds

    NASA Astrophysics Data System (ADS)

    Iman Zolanvari, S. M.; Laefer, Debra F.

    2016-09-01

    Laser scanning technology is a fast and reliable method to survey structures. However, the automatic conversion of such data into solid models for computation remains a major challenge, especially where non-rectilinear features are present. Since, openings and the overall dimensions of the buildings are the most critical elements in computational models for structural analysis, this article introduces the Slicing Method as a new, computationally-efficient method for extracting overall façade and window boundary points for reconstructing a façade into a geometry compatible for computational modelling. After finding a principal plane, the technique slices a façade into limited portions, with each slice representing a unique, imaginary section passing through a building. This is done along a façade's principal axes to segregate window and door openings from structural portions of the load-bearing masonry walls. The method detects each opening area's boundaries, as well as the overall boundary of the façade, in part, by using a one-dimensional projection to accelerate processing. Slices were optimised as 14.3 slices per vertical metre of building and 25 slices per horizontal metre of building, irrespective of building configuration or complexity. The proposed procedure was validated by its application to three highly decorative, historic brick buildings. Accuracy in excess of 93% was achieved with no manual intervention on highly complex buildings and nearly 100% on simple ones. Furthermore, computational times were less than 3 sec for data sets up to 2.6 million points, while similar existing approaches required more than 16 hr for such datasets.

  20. An implementation of a tree code on a SIMD, parallel computer

    NASA Technical Reports Server (NTRS)

    Olson, Kevin M.; Dorband, John E.

    1994-01-01

    We describe a fast tree algorithm for gravitational N-body simulation on SIMD parallel computers. The tree construction uses fast, parallel sorts. The sorted lists are recursively divided along their x, y and z coordinates. This data structure is a completely balanced tree (i.e., each particle is paired with exactly one other particle) and maintains good spatial locality. An implementation of this tree-building algorithm on a 16k processor Maspar MP-1 performs well and constitutes only a small fraction (approximately 15%) of the entire cycle of finding the accelerations. Each node in the tree is treated as a monopole. The tree search and the summation of accelerations also perform well. During the tree search, node data that is needed from another processor is simply fetched. Roughly 55% of the tree search time is spent in communications between processors. We apply the code to two problems of astrophysical interest. The first is a simulation of the close passage of two gravitationally, interacting, disk galaxies using 65,636 particles. We also simulate the formation of structure in an expanding, model universe using 1,048,576 particles. Our code attains speeds comparable to one head of a Cray Y-MP, so single instruction, multiple data (SIMD) type computers can be used for these simulations. The cost/performance ratio for SIMD machines like the Maspar MP-1 make them an extremely attractive alternative to either vector processors or large multiple instruction, multiple data (MIMD) type parallel computers. With further optimizations (e.g., more careful load balancing), speeds in excess of today's vector processing computers should be possible.

  1. Variable soft X-ray excesses in active galactic nuclei from nonthermal electron-positron pair cascades

    NASA Technical Reports Server (NTRS)

    Zdziarski, Andrzej A.; Coppi, Paolo S.

    1991-01-01

    In the present study of the formation of steep soft X-ray excesses that are superposed on flatter, hard X-ray power-law spectra in nonthermal electron-positron pair cascade sources, the soft excess in pair-cascade AGN models appears as a steep power law superposed on the tail of the UV bump and the flat nonthermal (hard X-ray) power law. The model-parameter space in which an excess in soft X-rays is visible is ascertained, and the time-variability of soft excesses in pair cascade models is examined. It is established that the parameter space in which soft excesses appear encompasses the range of preferred input parameters for a recently development Compton reflection model of UV and X-ray emission from the central engine of an AGN.

  2. Best Merge Region Growing Segmentation with Integrated Non-Adjacent Region Object Aggregation

    NASA Technical Reports Server (NTRS)

    Tilton, James C.; Tarabalka, Yuliya; Montesano, Paul M.; Gofman, Emanuel

    2012-01-01

    Best merge region growing normally produces segmentations with closed connected region objects. Recognizing that spectrally similar objects often appear in spatially separate locations, we present an approach for tightly integrating best merge region growing with non-adjacent region object aggregation, which we call Hierarchical Segmentation or HSeg. However, the original implementation of non-adjacent region object aggregation in HSeg required excessive computing time even for moderately sized images because of the required intercomparison of each region with all other regions. This problem was previously addressed by a recursive approximation of HSeg, called RHSeg. In this paper we introduce a refined implementation of non-adjacent region object aggregation in HSeg that reduces the computational requirements of HSeg without resorting to the recursive approximation. In this refinement, HSeg s region inter-comparisons among non-adjacent regions are limited to regions of a dynamically determined minimum size. We show that this refined version of HSeg can process moderately sized images in about the same amount of time as RHSeg incorporating the original HSeg. Nonetheless, RHSeg is still required for processing very large images due to its lower computer memory requirements and amenability to parallel processing. We then note a limitation of RHSeg with the original HSeg for high spatial resolution images, and show how incorporating the refined HSeg into RHSeg overcomes this limitation. The quality of the image segmentations produced by the refined HSeg is then compared with other available best merge segmentation approaches. Finally, we comment on the unique nature of the hierarchical segmentations produced by HSeg.

  3. EBLAST: an efficient high-compression image transformation 3. application to Internet image and video transmission

    NASA Astrophysics Data System (ADS)

    Schmalz, Mark S.; Ritter, Gerhard X.; Caimi, Frank M.

    2001-12-01

    A wide variety of digital image compression transforms developed for still imaging and broadcast video transmission are unsuitable for Internet video applications due to insufficient compression ratio, poor reconstruction fidelity, or excessive computational requirements. Examples include hierarchical transforms that require all, or large portion of, a source image to reside in memory at one time, transforms that induce significant locking effect at operationally salient compression ratios, and algorithms that require large amounts of floating-point computation. The latter constraint holds especially for video compression by small mobile imaging devices for transmission to, and compression on, platforms such as palmtop computers or personal digital assistants (PDAs). As Internet video requirements for frame rate and resolution increase to produce more detailed, less discontinuous motion sequences, a new class of compression transforms will be needed, especially for small memory models and displays such as those found on PDAs. In this, the third series of papers, we discuss the EBLAST compression transform and its application to Internet communication. Leading transforms for compression of Internet video and still imagery are reviewed and analyzed, including GIF, JPEG, AWIC (wavelet-based), wavelet packets, and SPIHT, whose performance is compared with EBLAST. Performance analysis criteria include time and space complexity and quality of the decompressed image. The latter is determined by rate-distortion data obtained from a database of realistic test images. Discussion also includes issues such as robustness of the compressed format to channel noise. EBLAST has been shown to perform superiorly to JPEG and, unlike current wavelet compression transforms, supports fast implementation on embedded processors with small memory models.

  4. 31 CFR 515.533 - Transactions incident to exportations from the United States and reexportations of 100% U.S...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... time, travel, or recreation in excess of that consistent with a full work schedule; and (3) The... activities does not include free time, travel, or recreation in excess of that consistent with a full work... travel to, from, or within Cuba. See paragraphs (e) and (f) for general licenses, and paragraph (g) for a...

  5. 31 CFR 515.533 - Transactions incident to exportations from the United States and reexportations of 100% U.S...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... time, travel, or recreation in excess of that consistent with a full work schedule; and (3) The... activities does not include free time, travel, or recreation in excess of that consistent with a full work... travel to, from, or within Cuba. See paragraphs (e) and (f) for general licenses, and paragraph (g) for a...

  6. 31 CFR 515.533 - Transactions incident to exportations from the United States and reexportations of 100% U.S...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... time, travel, or recreation in excess of that consistent with a full work schedule; and (3) The... activities does not include free time, travel, or recreation in excess of that consistent with a full work... travel to, from, or within Cuba. See paragraphs (e) and (f) for general licenses, and paragraph (g) for a...

  7. 31 CFR 515.533 - Transactions incident to exportations from the United States and reexportations of 100% U.S...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... time, travel, or recreation in excess of that consistent with a full work schedule; and (3) The... activities does not include free time, travel, or recreation in excess of that consistent with a full work... travel to, from, or within Cuba. See paragraphs (e) and (f) for general licenses, and paragraph (g) for a...

  8. 31 CFR 515.533 - Transactions incident to exportations from the United States and reexportations of 100% U.S...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... time, travel, or recreation in excess of that consistent with a full work schedule; and (3) The... activities does not include free time, travel, or recreation in excess of that consistent with a full work... travel to, from, or within Cuba. See paragraphs (e) and (f) for general licenses, and paragraph (g) for a...

  9. Design of an FPGA-Based Algorithm for Real-Time Solutions of Statistics-Based Positioning

    PubMed Central

    DeWitt, Don; Johnson-Williams, Nathan G.; Miyaoka, Robert S.; Li, Xiaoli; Lockhart, Cate; Lewellen, Tom K.; Hauck, Scott

    2010-01-01

    We report on the implementation of an algorithm and hardware platform to allow real-time processing of the statistics-based positioning (SBP) method for continuous miniature crystal element (cMiCE) detectors. The SBP method allows an intrinsic spatial resolution of ~1.6 mm FWHM to be achieved using our cMiCE design. Previous SBP solutions have required a postprocessing procedure due to the computation and memory intensive nature of SBP. This new implementation takes advantage of a combination of algebraic simplifications, conversion to fixed-point math, and a hierarchal search technique to greatly accelerate the algorithm. For the presented seven stage, 127 × 127 bin LUT implementation, these algorithm improvements result in a reduction from >7 × 106 floating-point operations per event for an exhaustive search to < 5 × 103 integer operations per event. Simulations show nearly identical FWHM positioning resolution for this accelerated SBP solution, and positioning differences of <0.1 mm from the exhaustive search solution. A pipelined field programmable gate array (FPGA) implementation of this optimized algorithm is able to process events in excess of 250 K events per second, which is greater than the maximum expected coincidence rate for an individual detector. In contrast with all detectors being processed at a centralized host, as in the current system, a separate FPGA is available at each detector, thus dividing the computational load. These methods allow SBP results to be calculated in real-time and to be presented to the image generation components in real-time. A hardware implementation has been developed using a commercially available prototype board. PMID:21197135

  10. Adaptive Wavelet Modeling of Geophysical Data

    NASA Astrophysics Data System (ADS)

    Plattner, A.; Maurer, H.; Dahmen, W.; Vorloeper, J.

    2009-12-01

    Despite the ever-increasing power of modern computers, realistic modeling of complex three-dimensional Earth models is still a challenging task and requires substantial computing resources. The overwhelming majority of current geophysical modeling approaches includes either finite difference or non-adaptive finite element algorithms, and variants thereof. These numerical methods usually require the subsurface to be discretized with a fine mesh to accurately capture the behavior of the physical fields. However, this may result in excessive memory consumption and computing times. A common feature of most of these algorithms is that the modeled data discretizations are independent of the model complexity, which may be wasteful when there are only minor to moderate spatial variations in the subsurface parameters. Recent developments in the theory of adaptive numerical solvers have the potential to overcome this problem. Here, we consider an adaptive wavelet based approach that is applicable to a large scope of problems, also including nonlinear problems. To the best of our knowledge such algorithms have not yet been applied in geophysics. Adaptive wavelet algorithms offer several attractive features: (i) for a given subsurface model, they allow the forward modeling domain to be discretized with a quasi minimal number of degrees of freedom, (ii) sparsity of the associated system matrices is guaranteed, which makes the algorithm memory efficient, and (iii) the modeling accuracy scales linearly with computing time. We have implemented the adaptive wavelet algorithm for solving three-dimensional geoelectric problems. To test its performance, numerical experiments were conducted with a series of conductivity models exhibiting varying degrees of structural complexity. Results were compared with a non-adaptive finite element algorithm, which incorporates an unstructured mesh to best fit subsurface boundaries. Such algorithms represent the current state-of-the-art in geoelectrical modeling. An analysis of the numerical accuracy as a function of the number of degrees of freedom revealed that the adaptive wavelet algorithm outperforms the finite element solver for simple and moderately complex models, whereas the results become comparable for models with spatially highly variable electrical conductivities. The linear dependency of the modeling error and the computing time proved to be model-independent. This feature will allow very efficient computations using large-scale models as soon as our experimental code is optimized in terms of its implementation.

  11. Modeling and Comparison of Options for the Disposal of Excess Weapons Plutonium in Russia

    DTIC Science & Technology

    2002-04-01

    fuel LWR cooling time LWR Pu load rate LWR net destruction frac ~ LWR reactors op life mox core frac Excess Separated Pu HTGR Cycle Pu in Waste LWR MOX...reflecting the cycle used in this type of reactor. For the HTGR , the entire core consists of plutonium fuel , therefore a core fraction is not specified...cooling time Time spent fuel unloaded from HTGR reactor must cool before permanently stored 3 years Mox core fraction Fraction of

  12. A COMPREHENSIVE CENSUS OF NEARBY INFRARED EXCESS STARS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cotten, Tara H.; Song, Inseok, E-mail: tara@physast.uga.edu, E-mail: song@physast.uga.edu

    The conclusion of the Wide-Field Infrared Survey Explorer ( WISE ) mission presents an opportune time to summarize the history of using excess emission in the infrared as a tracer of circumstellar material and exploit all available data for future missions such as the James Webb Space Telescope . We have compiled a catalog of infrared excess stars from peer-reviewed articles and perform an extensive search for new infrared excess stars by cross-correlating the Tycho-2 and all-sky WISE (AllWISE) catalogs. We define a significance of excess in four spectral type divisions and select stars showing greater than either 3 σmore » or 5 σ significance of excess in the mid- and far-infrared. Through procedures including spectral energy distribution fitting and various image analyses, each potential excess source was rigorously vetted to eliminate false positives. The infrared excess stars from the literature and the new stars found through the Tycho-2 and AllWISE cross-correlation produced nearly 500 “Prime” infrared excess stars, of which 74 are new sources of excess, and >1200 are “Reserved” stars, of which 950 are new sources of excess. The main catalog of infrared excess stars are nearby, bright, and either demonstrate excess in more than one passband or have infrared spectroscopy confirming the infrared excess. This study identifies stars that display a spectral energy distribution suggestive of a secondary or post-protoplanetary generation of dust, and they are ideal targets for future optical and infrared imaging observations. The final catalogs of stars summarize the past work using infrared excess to detect dust disks, and with the most extensive compilation of infrared excess stars (∼1750) to date, we investigate various relationships among stellar and disk parameters.« less

  13. Tidal flushing and wind driven circulation of Ahe atoll lagoon (Tuamotu Archipelago, French Polynesia) from in situ observations and numerical modelling.

    PubMed

    Dumas, F; Le Gendre, R; Thomas, Y; Andréfouët, S

    2012-01-01

    Hydrodynamic functioning and water circulation of the semi-closed deep lagoon of Ahe atoll (Tuamotu Archipelago, French Polynesia) were investigated using 1 year of field data and a 3D hydrodynamical model. Tidal amplitude averaged less than 30 cm, but tide generated very strong currents (2 ms(-1)) in the pass, creating a jet-like circulation that partitioned the lagoon into three residual circulation cells. The pass entirely flushed excess water brought by waves-induced radiation stress. Circulation patterns were computed for climatological meteorological conditions and summarized with stream function and flushing time. Lagoon hydrodynamics and general overturning circulation was driven by wind. Renewal time was 250 days, whereas the e-flushing time yielded a lagoon-wide 80-days average. Tide-driven flush through the pass and wind-driven overturning circulation designate Ahe as a wind-driven, tidally and weakly wave-flushed deep lagoon. The 3D model allows studying pearl oyster larvae dispersal in both realistic and climatological conditions for aquaculture applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Preliminary Evidence for an Emerging Nonmetropolitan Mortality Penalty in the United States

    PubMed Central

    Cosby, Arthur G.; Neaves, Tonya T.; Cossman, Ronald E.; Cossman, Jeralynn S.; James, Wesley L.; Feierabend, Neal; Mirvis, David M.; Jones, Carol A.; Farrigan, Tracey

    2008-01-01

    We discovered an emerging non-metropolitan mortality penalty by contrasting 37 years of age-adjusted mortality rates for metropolitan versus nonmetropolitan US counties. During the 1980s, annual metropolitan–nonmetropolitan differences averaged 6.2 excess deaths per 100000 nonmetropolitan population, or approximately 3600 excess deaths; however, by 2000 to 2004, the difference had increased more than 10 times to average 71.7 excess deaths, or approximately 35 000 excess deaths. We recommend that research be undertaken to evaluate and utilize our preliminary findings of an emerging US nonmetropolitan mortality penalty. PMID:18556611

  15. 3D Finite Element Analysis of Yixing CFRD Built on Inclined Mountain Slope

    NASA Astrophysics Data System (ADS)

    Sun, Da Wei; Zhang, Liang; Qing Yao, Hui; Wang, Kang Ping

    2018-05-01

    There are few CFRDs built on steep slope with dam height more than 50 m. So does the relative design and construction experience. The 75 m-high Yixing CFRD was built on steep mountain slope and the 45.9m-high gravity retaining wall was used to against dam sliding. Since the excessive deformation of dam body and perimetric joints would lead to failure of seal materials and cause water leakage, 3D nonlinear finite element stress-deformation analysis was carried out. 3D finite element mesh with 63875 elements including retaining wall and surrounding mountain was established by use of advanced grid discreteness technique. Large scales of equations solving method were adopted in the computer procedure and the calculation time was greatly reduced from former 40 hours to now 45 minutes. Therefore the behavior of the dam, retaining wall and the joint was obtained in a short time, and the results would be helpful to the design and construction of Yixing dam.

  16. Reversibility in Quantum Models of Stochastic Processes

    NASA Astrophysics Data System (ADS)

    Gier, David; Crutchfield, James; Mahoney, John; James, Ryan

    Natural phenomena such as time series of neural firing, orientation of layers in crystal stacking and successive measurements in spin-systems are inherently probabilistic. The provably minimal classical models of such stochastic processes are ɛ-machines, which consist of internal states, transition probabilities between states and output values. The topological properties of the ɛ-machine for a given process characterize the structure, memory and patterns of that process. However ɛ-machines are often not ideal because their statistical complexity (Cμ) is demonstrably greater than the excess entropy (E) of the processes they represent. Quantum models (q-machines) of the same processes can do better in that their statistical complexity (Cq) obeys the relation Cμ >= Cq >= E. q-machines can be constructed to consider longer lengths of strings, resulting in greater compression. With code-words of sufficiently long length, the statistical complexity becomes time-symmetric - a feature apparently novel to this quantum representation. This result has ramifications for compression of classical information in quantum computing and quantum communication technology.

  17. Extended Finite Element Method with Simplified Spherical Harmonics Approximation for the Forward Model of Optical Molecular Imaging

    PubMed Central

    Li, Wei; Yi, Huangjian; Zhang, Qitan; Chen, Duofang; Liang, Jimin

    2012-01-01

    An extended finite element method (XFEM) for the forward model of 3D optical molecular imaging is developed with simplified spherical harmonics approximation (SPN). In XFEM scheme of SPN equations, the signed distance function is employed to accurately represent the internal tissue boundary, and then it is used to construct the enriched basis function of the finite element scheme. Therefore, the finite element calculation can be carried out without the time-consuming internal boundary mesh generation. Moreover, the required overly fine mesh conforming to the complex tissue boundary which leads to excess time cost can be avoided. XFEM conveniences its application to tissues with complex internal structure and improves the computational efficiency. Phantom and digital mouse experiments were carried out to validate the efficiency of the proposed method. Compared with standard finite element method and classical Monte Carlo (MC) method, the validation results show the merits and potential of the XFEM for optical imaging. PMID:23227108

  18. Extended finite element method with simplified spherical harmonics approximation for the forward model of optical molecular imaging.

    PubMed

    Li, Wei; Yi, Huangjian; Zhang, Qitan; Chen, Duofang; Liang, Jimin

    2012-01-01

    An extended finite element method (XFEM) for the forward model of 3D optical molecular imaging is developed with simplified spherical harmonics approximation (SP(N)). In XFEM scheme of SP(N) equations, the signed distance function is employed to accurately represent the internal tissue boundary, and then it is used to construct the enriched basis function of the finite element scheme. Therefore, the finite element calculation can be carried out without the time-consuming internal boundary mesh generation. Moreover, the required overly fine mesh conforming to the complex tissue boundary which leads to excess time cost can be avoided. XFEM conveniences its application to tissues with complex internal structure and improves the computational efficiency. Phantom and digital mouse experiments were carried out to validate the efficiency of the proposed method. Compared with standard finite element method and classical Monte Carlo (MC) method, the validation results show the merits and potential of the XFEM for optical imaging.

  19. Influenza Excess Mortality from 1950–2000 in Tropical Singapore

    PubMed Central

    Lee, Vernon J.; Yap, Jonathan; Ong, Jimmy B. S.; Chan, Kwai-Peng; Lin, Raymond T. P.; Chan, Siew Pang; Goh, Kee Tai; Leo, Yee-Sin; Chen, Mark I-Cheng

    2009-01-01

    Introduction Tropical regions have been shown to exhibit different influenza seasonal patterns compared to their temperate counterparts. However, there is little information about the burden of annual tropical influenza epidemics across time, and the relationship between tropical influenza epidemics compared with other regions. Methods Data on monthly national mortality and population was obtained from 1947 to 2003 in Singapore. To determine excess mortality for each month, we used a moving average analysis for each month from 1950 to 2000. From 1972, influenza viral surveillance data was available. Before 1972, information was obtained from serial annual government reports, peer-reviewed journal articles and press articles. Results The influenza pandemics of 1957 and 1968 resulted in substantial mortality. In addition, there were 20 other time points with significant excess mortality. Of the 12 periods with significant excess mortality post-1972, only one point (1988) did not correspond to a recorded influenza activity. For the 8 periods with significant excess mortality periods before 1972 excluding the pandemic years, 2 years (1951 and 1953) had newspaper reports of increased pneumonia deaths. Excess mortality could be observed in almost all periods with recorded influenza outbreaks but did not always exceed the 95% confidence limits of the baseline mortality rate. Conclusion Influenza epidemics were the likely cause of most excess mortality periods in post-war tropical Singapore, although not every epidemic resulted in high mortality. It is therefore important to have good influenza surveillance systems in place to detect influenza activity. PMID:19956611

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sattari, Sulimon, E-mail: ssattari2@ucmerced.edu; Chen, Qianting, E-mail: qchen2@ucmerced.edu; Mitchell, Kevin A., E-mail: kmitchell@ucmerced.edu

    Topological approaches to mixing are important tools to understand chaotic fluid flows, ranging from oceanic transport to the design of micro-mixers. Typically, topological entropy, the exponential growth rate of material lines, is used to quantify topological mixing. Computing topological entropy from the direct stretching rate is computationally expensive and sheds little light on the source of the mixing. Earlier approaches emphasized that topological entropy could be viewed as generated by the braiding of virtual, or “ghost,” rods stirring the fluid in a periodic manner. Here, we demonstrate that topological entropy can also be viewed as generated by the braiding ofmore » ghost rods following heteroclinic orbits instead. We use the machinery of homotopic lobe dynamics, which extracts symbolic dynamics from finite-length pieces of stable and unstable manifolds attached to fixed points of the fluid flow. As an example, we focus on the topological entropy of a bounded, chaotic, two-dimensional, double-vortex cavity flow. Over a certain parameter range, the topological entropy is primarily due to the braiding of a period-three orbit. However, this orbit does not explain the topological entropy for parameter values where it does not exist, nor does it explain the excess of topological entropy for the entire range of its existence. We show that braiding by heteroclinic orbits provides an accurate computation of topological entropy when the period-three orbit does not exist, and that it provides an explanation for some of the excess topological entropy when the period-three orbit does exist. Furthermore, the computation of symbolic dynamics using heteroclinic orbits has been automated and can be used to compute topological entropy for a general 2D fluid flow.« less

  1. Using heteroclinic orbits to quantify topological entropy in fluid flows

    NASA Astrophysics Data System (ADS)

    Sattari, Sulimon; Chen, Qianting; Mitchell, Kevin A.

    2016-03-01

    Topological approaches to mixing are important tools to understand chaotic fluid flows, ranging from oceanic transport to the design of micro-mixers. Typically, topological entropy, the exponential growth rate of material lines, is used to quantify topological mixing. Computing topological entropy from the direct stretching rate is computationally expensive and sheds little light on the source of the mixing. Earlier approaches emphasized that topological entropy could be viewed as generated by the braiding of virtual, or "ghost," rods stirring the fluid in a periodic manner. Here, we demonstrate that topological entropy can also be viewed as generated by the braiding of ghost rods following heteroclinic orbits instead. We use the machinery of homotopic lobe dynamics, which extracts symbolic dynamics from finite-length pieces of stable and unstable manifolds attached to fixed points of the fluid flow. As an example, we focus on the topological entropy of a bounded, chaotic, two-dimensional, double-vortex cavity flow. Over a certain parameter range, the topological entropy is primarily due to the braiding of a period-three orbit. However, this orbit does not explain the topological entropy for parameter values where it does not exist, nor does it explain the excess of topological entropy for the entire range of its existence. We show that braiding by heteroclinic orbits provides an accurate computation of topological entropy when the period-three orbit does not exist, and that it provides an explanation for some of the excess topological entropy when the period-three orbit does exist. Furthermore, the computation of symbolic dynamics using heteroclinic orbits has been automated and can be used to compute topological entropy for a general 2D fluid flow.

  2. Combined influence of media use on subjective health in elementary school children in Japan: a population-based study.

    PubMed

    Nakamura, Harunobu; Ohara, Kumiko; Kouda, Katsuyasu; Fujita, Yuki; Mase, Tomoki; Miyawaki, Chiemi; Okita, Yoshimitsu; Ishikawa, Tetsuya

    2012-06-13

    In recent years in Japan, electronic games, home computers, and the internet have assumed an important place in people's lives, even for elementary school children. Subjective health complaints have also become a problem among children. In the present study, we investigated the relationship between media use and health status in elementary school children in Japan. A cross-sectional school-based population survey was conducted in 2009 with a sample of fourth-, fifth-, and sixth-grade children (age range: 10-12 years old) in elementary schools in Japan (n = 3,464). Self-reported health, lifestyle habits, and time spent using media were assessed. The use of games, television, and personal computers was significantly associated with lifestyle (p < 0.05) and subjective health (p < 0.05). In addition, the use of games, the use of television, and the use of personal computers were mutually associated. The greater the number of media used for more than 1 hour was, the higher the odds ratio of the association of media use with unhealthy lifestyle and subjective health complaints was. The plural use of these media had stronger associations with unhealthy lifestyle and subjective health complaints. Game, television, and personal-computer use were mutually associated, and the plural use of these media had stronger associations with unhealthy lifestyle and subjective health complaints. Excessive use of media might be a risk for unhealthy lifestyle and subjective health complaints.

  3. Combined influence of media use on subjective health in elementary school children in Japan: a population-based study

    PubMed Central

    2012-01-01

    Background In recent years in Japan, electronic games, home computers, and the internet have assumed an important place in people’s lives, even for elementary school children. Subjective health complaints have also become a problem among children. In the present study, we investigated the relationship between media use and health status in elementary school children in Japan. Methods A cross-sectional school-based population survey was conducted in 2009 with a sample of fourth-, fifth-, and sixth-grade children (age range: 10–12 years old) in elementary schools in Japan (n = 3,464). Self-reported health, lifestyle habits, and time spent using media were assessed. Results The use of games, television, and personal computers was significantly associated with lifestyle (p < 0.05) and subjective health (p < 0.05). In addition, the use of games, the use of television, and the use of personal computers were mutually associated. The greater the number of media used for more than 1 hour was, the higher the odds ratio of the association of media use with unhealthy lifestyle and subjective health complaints was. The plural use of these media had stronger associations with unhealthy lifestyle and subjective health complaints. Conclusions Game, television, and personal-computer use were mutually associated, and the plural use of these media had stronger associations with unhealthy lifestyle and subjective health complaints. Excessive use of media might be a risk for unhealthy lifestyle and subjective health complaints. PMID:22694807

  4. Racial and ethnic disparities in hospital care resulting from air pollution in excess of federal standards.

    PubMed

    Hackbarth, Andrew D; Romley, John A; Goldman, Dana P

    2011-10-01

    This study investigates racial and ethnic disparities in hospital admission and emergency room visit rates resulting from exposure to ozone and fine particulate matter levels in excess of federal standards ("excess attributable risk"). We generate zip code-level ambient pollution exposures and hospital event rates using state datasets, and use pollution impact estimates in the epidemiological literature to calculate excess attributable risk for racial/ethnic groups in California over 2005-2007. We find that black residents experienced roughly 2.5 times the excess attributable risk of white residents. Hispanic residents were exposed to the highest levels of pollution, but experienced similar excess attributable risk to whites. Asian/Pacific Islander residents had substantially lower excess attributable risk compared to white. We estimate the distinct contributions of exposure and other factors to these results, and find that factors other than exposure can be critical determinants of pollution-related disparities. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Bayer Digester Optimization Studies using Computer Techniques

    NASA Astrophysics Data System (ADS)

    Kotte, Jan J.; Schleider, Victor H.

    Theoretically required heat transfer performance by the multistaged flash heat reclaim system of a high pressure Bayer digester unit is determined for various conditions of discharge temperature, excess flash vapor and indirect steam addition. Solution of simultaneous heat balances around the digester vessels and the heat reclaim system yields the magnitude of available heat for representation of each case on a temperature-enthalpy diagram, where graphical fit of the number of flash stages fixes the heater requirements. Both the heat balances and the trial-and-error graphical solution are adapted to solution by digital computer techniques.

  6. Thermodynamic properties of a high pressure subcritical UF6/He gas volume (irradiated by an external source)

    NASA Technical Reports Server (NTRS)

    Sterritt, D. E.; Lalos, G. T.; Schneider, R. T.

    1976-01-01

    A computer simulation study concerning a compressed fissioning UF6 gas is presented. The compression is to be achieved by a ballistic piston compressor. Data on UF6 obtained with this compressor were incorporated in the simulation study. As a neutron source to create the fission events in the compressed gas, a fast burst reactor was considered. The conclusion is that it takes a neutron flux in excess of 10 to the 15th power n/sec sq cm to produce measurable increases in pressure and temperature, while a flux in excess of 10 to 19th power n/sq cm sec would probably damage the compressor.

  7. Thermodynamic properties of a high pressure subcritical UF/sub 6/He gas volume (irradiated by an external source)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sterritt, D.E.; Lalos, G.T.; Schneider, R.T.

    1976-12-01

    A computer simulation study concerning a compressed fissioning UF/sub 6/ gas is presented. The compression is to be achieved by a ballistic piston compressor. Data on UF/sub 6/ obtained with this compressor were incorporated in the simulation study. As a neutron source to create the fission events in the compressed gas, a fast burst reactor was considered. The conclusion is that it takes a neutron flux in excess of 10/sup 15/ n/cm/sup 2/-s to produce measurable increases in pressure and temperature, while a flux in excess of 10/sup 19/ n/cm/sup 2/-s would probably damage the compressor.

  8. Health impacts of Facebook usage and mobile texting among undergraduate dental students: it's time to understand the difference between usage and an excessive use.

    PubMed

    Lee, Y L; Verma, R K; Yadav, H; Barua, A

    2016-11-01

    Facebook and mobile texting are prevalent in the lives of almost every student. However, little is known about the relationship between Facebook usage or mobile texting and their impacts on health amongst undergraduate dental students. In this study, excessive Facebook use and excessive mobile texting were studied as they relate to impacts on health. A cross-sectional study was conducted at a private university in Malaysia. A total of 188 undergraduate dental students were interviewed using a pre-tested and self-rated questionnaire. Data collected from participants were analysed using SPSS version 18.0. Chi-square test, Fisher's exact test and multiple logistic regression analyses were applied to study the relationship between explanatory variables and excessive Facebook use and excessive mobile texting. The prevalence of excessive Facebook use and excessive mobile texting amongst undergraduate dental students was found to be 33.2% and 33.0%, respectively. According to a multivariate analysis, texting habits, such as the presence of daytime sleepiness after texting late at night (aOR = 2.682, 95% CI = 1.142-6.301) and the presence of anxious feelings if students failed to receive a timely response (aOR = 3.819, 95% CI = 1.580-9.230), were determined to be significant predictors of excessive mobile texting. Excessive Facebook use was found to be significantly related to three variables as follows: fewer numbers of close friends (aOR = 2.275, 95% CI = 1.057-4.898), the checking of updates on the Facebook walls of their friends (aOR = 2.582, 95% CI = 1.189-5.605) and the absence of active and vigorous feelings during Facebook use (aOR = 3.401, 95% CI = 1.233-9.434). Approximately one-third of undergraduate dental students in this study experienced excessive Facebook use and/or excessive mobile texting. Health education and promotion should be instituted to create awareness, whilst students should be advised to practise self-control with respect to both mobile texting and Facebook usage. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Ratio of produced gas to produced water from DOE's EDNA Delcambre No. 1 geopressured-geothermal aquifer gas well test

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rogers, L.A.; Randolph, P.L.

    1979-01-01

    A paper presented by the Institute of Gas Technology (IGT) at the Third Geopressured-Geothermal Energy Conference hypothesized that the high ratio of produced gas to produced water from the No. 1 sand in the Edna Delcambre No. 1 well was due to free gas trapped in pores by imbibition over geological time. This hypothesis was examined in relation to preliminary test data which reported only average gas to water ratios over the roughly 2-day steps in flow rate. Subsequent public release of detailed test data revealed substantial departures from the previously reported computer simulation results. Also, data now in themore » public domain reveal the existence of a gas cap on the aquifier tested. This paper describes IGT's efforts to match the observed gas/water production with computer simulation. Two models for the occurrence and production of gas in excess of that dissolved in the brine have been used. One model considers the gas to be dispersed in pores by imbibition, and the other model considers the gas as a nearby free gas cap above the aquifier. The studies revealed that the dispersed gas model characteristically gave the wrong shape to plots of gas production on the gas/water ratio plots such that no reasonable match to the flow data could be achieved. The free gas cap model gave a characteristically better shape to the production plots and could provide an approximate fit to the data of the edge of the free gas cap is only about 400 feet from the well.Because the geological structure maps indicate the free gas cap to be several thousand feet away and the computer simulation results match the distance to the nearby Delcambre Nos. 4 and 4A wells, it appears that the source of the excess free gas in the test of the No. 1 sand may be from these nearby wells. The gas source is probably a separate gas zone and is brought into contact with the No. 1 sand via a conduit around the No. 4 well.« less

  10. High-frequency video capture and a computer program with frame-by-frame angle determination functionality as tools that support judging in artistic gymnastics.

    PubMed

    Omorczyk, Jarosław; Nosiadek, Leszek; Ambroży, Tadeusz; Nosiadek, Andrzej

    2015-01-01

    The main aim of this study was to verify the usefulness of selected simple methods of recording and fast biomechanical analysis performed by judges of artistic gymnastics in assessing a gymnast's movement technique. The study participants comprised six artistic gymnastics judges, who assessed back handsprings using two methods: a real-time observation method and a frame-by-frame video analysis method. They also determined flexion angles of knee and hip joints using the computer program. In the case of the real-time observation method, the judges gave a total of 5.8 error points with an arithmetic mean of 0.16 points for the flexion of the knee joints. In the high-speed video analysis method, the total amounted to 8.6 error points and the mean value amounted to 0.24 error points. For the excessive flexion of hip joints, the sum of the error values was 2.2 error points and the arithmetic mean was 0.06 error points during real-time observation. The sum obtained using frame-by-frame analysis method equaled 10.8 and the mean equaled 0.30 error points. Error values obtained through the frame-by-frame video analysis of movement technique were higher than those obtained through the real-time observation method. The judges were able to indicate the number of the frame in which the maximal joint flexion occurred with good accuracy. Using the real-time observation method as well as the high-speed video analysis performed without determining the exact angle for assessing movement technique were found to be insufficient tools for improving the quality of judging.

  11. Level II scour analysis for Bridge 32 (NFIEVT012A0032) on State Route 12A, crossing the Dog River, Northfield, Vermont

    USGS Publications Warehouse

    Boehmler, Erick M.; Ivanoff, Michael A.

    1997-01-01

    section of the scour computed at the bridge is presented in figure 8. Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

  12. Developmental Programming: Impact of Prenatal Testosterone Excess on Insulin Sensitivity, Adiposity, and Free Fatty Acid Profile in Postpubertal Female Sheep

    PubMed Central

    Veiga-Lopez, A.; Moeller, J.; Patel, D.; Ye, W.; Pease, A.; Kinns, J.

    2013-01-01

    Prenatal T excess causes reproductive and metabolic disruptions including insulin resistance, attributes of women with polycystic ovary syndrome. This study tested whether increases in visceral adiposity, adipocyte size, and total free fatty acids underlie the insulin resistance seen in prenatal T-treated female sheep. At approximately 16 months of age, insulin resistance and adipose tissue partitioning were determined via hyperinsulinemic euglycemic clamp and computed tomography, respectively, in control and prenatal T-treated females. Three months later, adipocyte size and free fatty acid composition were determined. Results revealed that at the postpubertal time points tested, insulin sensitivity was increased, visceral adiposity and adipocyte size in both the sc and the visceral compartments were reduced, and circulating palmitic acid was increased in prenatal T-treated females relative to controls. In parallel studies, 20-month-old prenatal T-treated females tended to have increased basal insulin to glucose ratio. Relative to earlier findings of reduced insulin sensitivity of prenatal T-treated females during early life and adulthood, these findings of increased insulin sensitivity and reduced adiposity postpubertally are suggestive of a period of developmental adaptation. The disruption observed in free fatty acid metabolism a few months later correspond to a time point when the insulin sensitivity indices of prenatal T-treated animals appear to shift toward insulin resistance. In summary, current findings of improved insulin sensitivity and reduced visceral adiposity in postpubertal prenatal T-treated sheep relative to our earlier findings of reduced insulin sensitivity during early postnatal life and adulthood are indicative of a period of developmental adaptation. PMID:23525243

  13. Comparing Neuromorphic Solutions in Action: Implementing a Bio-Inspired Solution to a Benchmark Classification Task on Three Parallel-Computing Platforms

    PubMed Central

    Diamond, Alan; Nowotny, Thomas; Schmuker, Michael

    2016-01-01

    Neuromorphic computing employs models of neuronal circuits to solve computing problems. Neuromorphic hardware systems are now becoming more widely available and “neuromorphic algorithms” are being developed. As they are maturing toward deployment in general research environments, it becomes important to assess and compare them in the context of the applications they are meant to solve. This should encompass not just task performance, but also ease of implementation, speed of processing, scalability, and power efficiency. Here, we report our practical experience of implementing a bio-inspired, spiking network for multivariate classification on three different platforms: the hybrid digital/analog Spikey system, the digital spike-based SpiNNaker system, and GeNN, a meta-compiler for parallel GPU hardware. We assess performance using a standard hand-written digit classification task. We found that whilst a different implementation approach was required for each platform, classification performances remained in line. This suggests that all three implementations were able to exercise the model's ability to solve the task rather than exposing inherent platform limits, although differences emerged when capacity was approached. With respect to execution speed and power consumption, we found that for each platform a large fraction of the computing time was spent outside of the neuromorphic device, on the host machine. Time was spent in a range of combinations of preparing the model, encoding suitable input spiking data, shifting data, and decoding spike-encoded results. This is also where a large proportion of the total power was consumed, most markedly for the SpiNNaker and Spikey systems. We conclude that the simulation efficiency advantage of the assessed specialized hardware systems is easily lost in excessive host-device communication, or non-neuronal parts of the computation. These results emphasize the need to optimize the host-device communication architecture for scalability, maximum throughput, and minimum latency. Moreover, our results indicate that special attention should be paid to minimize host-device communication when designing and implementing networks for efficient neuromorphic computing. PMID:26778950

  14. Effects of scarcity and excess of larval food on life history traits of Aedes aegypti (Diptera: Culicidae).

    PubMed

    Romeo Aznar, Victoria; Alem, Iris; De Majo, María Sol; Byttebier, Barbara; Solari, Hernán G; Fischer, Sylvia

    2018-06-01

    Few studies have assessed the effects of food scarcity or excess on the life history traits of Aedes aegypti (L.) (Diptera: Culicidae) independently from larval density. We assessed immature survival, development time, and adult size in relation to food availability. We reared cohorts of 30 Ae. aegypti larvae from newly hatched to adult emergence with different food availability. Food conditions were kept constant by transferring larvae each day to a new food solution. Immature development was completed by some individuals in all treatments. The shortest development time, the largest adults, and the highest survival were observed at intermediate food levels. The most important effects of food scarcity were an extension in development time, a decrease in the size of adults, and a slight decrease in survival, while the most important effects of food excess were an important decrease in survival and a slight decrease in the size of adults. The variability in development time and adult size within sex and treatment increased at decreasing food availability. The results suggest that although the studied population has adapted to a wide range of food availabilities, both scarcity and excess of food have important negative impacts on fitness. © 2018 The Society for Vector Ecology.

  15. Excessive Time on Social Networking Sites and Disordered Eating Behaviors Among Undergraduate Students: Appearance and Weight Esteem as Mediating Pathways.

    PubMed

    Murray, Marisa; Maras, Danijela; Goldfield, Gary S

    2016-12-01

    Social networking sites (SNS) are a popular form of communication among undergraduate students. Body image concerns and disordered eating behaviors are also quite prevalent among this population. Maladaptive use of SNS has been associated with disordered eating behaviors; however, the mechanisms remain unclear. The present study examined if body image concerns (e.g., appearance and weight esteem) mediate the relationship between excessive time spent on SNS and disordered eating behaviors (restrained and emotional eating). The sample included 383 (70.2 percent female) undergraduate students (mean age = 23.08 years, standard deviation = 3.09) who completed self-report questionnaires related to SNS engagement, body image, disordered eating behaviors, and demographics. Parallel multiple mediation and moderated mediation analyses revealed that lower weight and appearance esteem mediated the relationship between excessive time on SNS and restrained eating for males and females, whereas appearance esteem mediated the relationship between excessive time on SNS and emotional eating for females only. The study adds to the literature by highlighting mediational pathways and gender differences. Intervention research is needed to determine if teaching undergraduate students more adaptive ways of using SNS or reducing exposure to SNS reduces body dissatisfaction and disordered eating in this high-risk population.

  16. Estimate of overdiagnosis of breast cancer due to mammography after adjustment for lead time. A service screening study in Italy

    PubMed Central

    Paci, Eugenio; Miccinesi, Guido; Puliti, Donella; Baldazzi, Paola; De Lisi, Vincenzo; Falcini, Fabio; Cirilli, Claudia; Ferretti, Stefano; Mangone, Lucia; Finarelli, Alba Carola; Rosso, Stefano; Segnan, Nereo; Stracci, Fabrizio; Traina, Adele; Tumino, Rosario; Zorzi, Manuel

    2006-01-01

    Introduction Excess of incidence rates is the expected consequence of service screening. The aim of this paper is to estimate the quota attributable to overdiagnosis in the breast cancer screening programmes in Northern and Central Italy. Methods All patients with breast cancer diagnosed between 50 and 74 years who were resident in screening areas in the six years before and five years after the start of the screening programme were included. We calculated a corrected-for-lead-time number of observed cases for each calendar year. The number of observed incident cases was reduced by the number of screen-detected cases in that year and incremented by the estimated number of screen-detected cases that would have arisen clinically in that year. Results In total we included 13,519 and 13,999 breast cancer cases diagnosed in the pre-screening and screening years, respectively. In total, the excess ratio of observed to predicted in situ and invasive cases was 36.2%. After correction for lead time the excess ratio was 4.6% (95% confidence interval 2 to 7%) and for invasive cases only it was 3.2% (95% confidence interval 1 to 6%). Conclusion The remaining excess of cancers after individual correction for lead time was lower than 5%. PMID:17147789

  17. 22 CFR Appendix A to Part 226 - Contract Provisions

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Construction”). Under this Act, contractors shall be required to pay wages to laborers and mechanics at a rate... in excess of $2500 for other such contracts that involve the employment of mechanics or laborers... section 102 of the Act, each contractor shall be required to compute the wages of every mechanic and...

  18. 22 CFR Appendix A to Part 226 - Contract Provisions

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Construction”). Under this Act, contractors shall be required to pay wages to laborers and mechanics at a rate... in excess of $2500 for other such contracts that involve the employment of mechanics or laborers... section 102 of the Act, each contractor shall be required to compute the wages of every mechanic and...

  19. 22 CFR Appendix A to Part 226 - Contract Provisions

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Construction”). Under this Act, contractors shall be required to pay wages to laborers and mechanics at a rate... in excess of $2500 for other such contracts that involve the employment of mechanics or laborers... section 102 of the Act, each contractor shall be required to compute the wages of every mechanic and...

  20. 26 CFR 1.1251-2 - Excess deductions account.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... business of farming which is held for draft, breeding, dairy, or sporting purposes regardless of the period... of breeding herd to which section 1251(c)(1) applies (computed before applying limitation) 14,000 (c... animal, such as for stud, breeding, and veterinary services, as well as all amounts paid or incurred with...

  1. 26 CFR 1.1251-2 - Excess deductions account.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... business of farming which is held for draft, breeding, dairy, or sporting purposes regardless of the period... of breeding herd to which section 1251(c)(1) applies (computed before applying limitation) 14,000 (c... animal, such as for stud, breeding, and veterinary services, as well as all amounts paid or incurred with...

  2. 26 CFR 1.1251-2 - Excess deductions account.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... business of farming which is held for draft, breeding, dairy, or sporting purposes regardless of the period... of breeding herd to which section 1251(c)(1) applies (computed before applying limitation) 14,000 (c... animal, such as for stud, breeding, and veterinary services, as well as all amounts paid or incurred with...

  3. 26 CFR 1.1251-2 - Excess deductions account.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... business of farming which is held for draft, breeding, dairy, or sporting purposes regardless of the period... of breeding herd to which section 1251(c)(1) applies (computed before applying limitation) 14,000 (c... animal, such as for stud, breeding, and veterinary services, as well as all amounts paid or incurred with...

  4. Attending Behaviors of ADHD Children in Math and Reading Using Various Types of Software.

    ERIC Educational Resources Information Center

    Ford, Mary Jane; And Others

    1993-01-01

    Compared the effects of using various computer software programs on the attending behavior of children with attention-deficit hyperactive disorder (ADHD). Found that the attention of ADHD children increased while they used software with a game format when animation was not excessive. Other factors affecting nonattending behaviors included the…

  5. Deep FIFO Surge Buffer

    NASA Technical Reports Server (NTRS)

    Temple, Gerald; Siegel, Marc; Amitai, Zwie

    1991-01-01

    First-in/first-out (FIFO) temporarily stores short surges of data generated by data-acquisition system at excessively high rate and releases data at lower rate suitable for processing by computer. Size and complexity reduced while capacity enhanced by use of newly developed, sophisticated integrated circuits and by "byte-folding" scheme doubling effective depth and data rate.

  6. 45 CFR 2543.84 - Contract Work Hours and Safety Standards Act.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... contracts and in excess of $2500 for other contracts that involve the employment of mechanics or laborers... Section 102 of the Act, each contractor shall be required to compute the wages of every mechanic and... to construction work and provides that no laborer or mechanic shall be required to work in...

  7. 45 CFR 2543.84 - Contract Work Hours and Safety Standards Act.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... contracts and in excess of $2500 for other contracts that involve the employment of mechanics or laborers... Section 102 of the Act, each contractor shall be required to compute the wages of every mechanic and... to construction work and provides that no laborer or mechanic shall be required to work in...

  8. 45 CFR 2543.84 - Contract Work Hours and Safety Standards Act.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... contracts and in excess of $2500 for other contracts that involve the employment of mechanics or laborers... Section 102 of the Act, each contractor shall be required to compute the wages of every mechanic and... to construction work and provides that no laborer or mechanic shall be required to work in...

  9. 45 CFR 2543.84 - Contract Work Hours and Safety Standards Act.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... contracts and in excess of $2500 for other contracts that involve the employment of mechanics or laborers... Section 102 of the Act, each contractor shall be required to compute the wages of every mechanic and... to construction work and provides that no laborer or mechanic shall be required to work in...

  10. 18 CFR 367.23 - Transactions with non-associate companies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... excess or deficiency of the cost on servicing the non-associate companies must be charged to account 458... charged to account 458.4 (§ 367.4584). In computing charges to associate companies for any calendar year, any net credit in this account must be deducted from amounts reimbursable by associate companies as...

  11. 7 CFR 3203.3 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... repair or enhance its operability. City, town, or local government entity in a rural area as defined in 7...) and fax machines. This term may also include computer software where the transfer of a license is... government entity located in a rural area as defined in 7 U.S.C. 1991(a)(13)(A) that may receive excess...

  12. Development a fluvial detachment rate model to predict the erodibility of cohesive soils under the influence of seepage

    USDA-ARS?s Scientific Manuscript database

    Seepage influences the erodibility of streambanks, streambeds, dams, and embankments. Usually the erosion rate of cohesive soils due to fluvial forces is computed using an excess shear stress model, dependent on two major soil parameters: the critical shear stress (tc) and the erodibility coefficie...

  13. 76 FR 45710 - Pay in Nonforeign Areas

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-01

    ... for the purpose of computing nonforeign area COLAs and post differentials, a retained rate established... limited by the normally applicable Executive Schedule level IV (EX-IV) cap on special rates ($155,500 in... special rate in excess of the EX-IV cap at the end of the transition period must be converted to a...

  14. 7 CFR § 3203.7 - Title.

    Code of Federal Regulations, 2010 CFR

    2018-01-01

    ... 7 Agriculture 15 2018-01-01 2018-01-01 false Title. § 3203.7 Section § 3203.7 Agriculture Regulations of the Department of Agriculture (Continued) OFFICE OF PROCUREMENT AND PROPERTY MANAGEMENT... PURSUANT TO SECTION 14220 OF THE 2008 FARM BILL § 3203.7 Title. Title of ownership to excess computers or...

  15. Polyphony: A Workflow Orchestration Framework for Cloud Computing

    NASA Technical Reports Server (NTRS)

    Shams, Khawaja S.; Powell, Mark W.; Crockett, Tom M.; Norris, Jeffrey S.; Rossi, Ryan; Soderstrom, Tom

    2010-01-01

    Cloud Computing has delivered unprecedented compute capacity to NASA missions at affordable rates. Missions like the Mars Exploration Rovers (MER) and Mars Science Lab (MSL) are enjoying the elasticity that enables them to leverage hundreds, if not thousands, or machines for short durations without making any hardware procurements. In this paper, we describe Polyphony, a resilient, scalable, and modular framework that efficiently leverages a large set of computing resources to perform parallel computations. Polyphony can employ resources on the cloud, excess capacity on local machines, as well as spare resources on the supercomputing center, and it enables these resources to work in concert to accomplish a common goal. Polyphony is resilient to node failures, even if they occur in the middle of a transaction. We will conclude with an evaluation of a production-ready application built on top of Polyphony to perform image-processing operations of images from around the solar system, including Mars, Saturn, and Titan.

  16. [Clinical characteristics of computer game and internet addiction in persons seeking treatment in an outpatient clinic for computer game addiction].

    PubMed

    Beutel, Manfred E; Hoch, Christina; Wölfling, Klaus; Müller, Kai W

    2011-01-01

    Since March 2008 we have offered outpatient treatment for computer game and internet addiction. This article presents the assessment and clinical characterization of the first cohort of one year. The reasons for seeking help (phone consultations, N=346) as well as sociodemographic and psychometric characteristics (N=131) (assessment of computer game addiction; SCL-90R) are presented. Consultation was initiated mainly by relatives--mostly the mothers (86%); 48% report achievement failure and social isolation, lack of control (38%) and conflicts within the family (33%). Two-thirds of the mainly male (96%) patients (N=131) with an average age of 22 (range 13-47) years met the criteria for pathological computer gaming, characterized by an excessive number of hours and preoccupation with gaming, high distress, and unemployment. Symptoms resemble those of other addiction disorders. The consequences for disorder-specific treatment concepts and research are discussed.

  17. Variation of Time Domain Failure Probabilities of Jack-up with Wave Return Periods

    NASA Astrophysics Data System (ADS)

    Idris, Ahmad; Harahap, Indra S. H.; Ali, Montassir Osman Ahmed

    2018-04-01

    This study evaluated failure probabilities of jack up units on the framework of time dependent reliability analysis using uncertainty from different sea states representing different return period of the design wave. Surface elevation for each sea state was represented by Karhunen-Loeve expansion method using the eigenfunctions of prolate spheroidal wave functions in order to obtain the wave load. The stochastic wave load was propagated on a simplified jack up model developed in commercial software to obtain the structural response due to the wave loading. Analysis of the stochastic response to determine the failure probability in excessive deck displacement in the framework of time dependent reliability analysis was performed by developing Matlab codes in a personal computer. Results from the study indicated that the failure probability increases with increase in the severity of the sea state representing a longer return period. Although the results obtained are in agreement with the results of a study of similar jack up model using time independent method at higher values of maximum allowable deck displacement, it is in contrast at lower values of the criteria where the study reported that failure probability decreases with increase in the severity of the sea state.

  18. The incidence of leukemia, lymphoma, and multiple myeloma among atomic bomb survivors: 1950 – 2001

    PubMed Central

    Hsu, Wan-Ling; Preston, Dale L.; Soda, Midori; Sugiyama, Hiromi; Funamoto, Sachiyo; Kodama, Kazunori; Kimura, Akiro; Kamada, Nanao; Dohy, Hiroo; Tomonaga, Masao; Iwanaga, Masako; Miyazaki, Yasushi; Cullings, Harry M.; Suyama, Akihiko; Ozasa, Kotaro; Shore, Roy E.; Mabuchi, Kiyohiko

    2013-01-01

    A marked increase in leukemia risks was the first and most striking late effect of radiation exposure seen among the Hiroshima and Nagasaki atomic bomb survivors. This paper presents analyses of radiation effects on leukemia, lymphoma, and multiple myeloma incidence in the Life Span Study cohort of atomic bomb survivors updated 14 years since the last comprehensive report on these malignancies. These analyses make use of tumor- and leukemia-registry-based incidence data on 113,011 cohort members with 3.6 million person-years of follow-up from late 1950 through the end of 2001. In addition to a detailed analysis of the excess risk for all leukemias other than chronic lymphocytic leukemia or adult T-cell leukemia (neither of which appear to be radiation-related), we present results for the major hematopoietic malignancy types: acute lymphoblastic leukemia, chronic lymphocytic leukemia, acute myeloid leukemia, chronic myeloid leukemia, adult T-cell leukemia, Hodgkin and non-Hodgkin lymphoma, and multiple myeloma. Poisson regression methods were used to characterize the shape of the radiation dose response relationship and, to the extent the data allowed, to investigate variation in the excess risks with sex, attained age, exposure age, and time since exposure. In contrast to the previous report that focused on describing excess absolute rates, we considered both excess absolute rate (EAR) and excess relative risk (ERR) models and found that ERR models can often provide equivalent and sometimes more parsimonious descriptions of the excess risk than EAR models. The leukemia results indicated that there was a non-linear dose response for leukemias other than chronic lymphocytic leukemia or adult T-cell leukemia, which varied markedly with time and age at exposure, with much of the evidence for this non-linearity arising from the acute myeloid leukemia risks. Although the leukemia excess risks generally declined with attained age or time since exposure, there was evidence that the radiation-associated excess leukemia risks, especially for acute myeloid leukemia, had persisted throughout the follow-up period out to – 55 years after the bombings. As in earlier analyses, there was a weak suggestion of a radiation dose response for non-Hodgkin lymphoma among men with no indication of such an effect among women. There was no evidence of radiation-associated excess risks for either Hodgkin lymphoma or multiple myeloma. PMID:23398354

  19. Bayesian Travel Time Inversion adopting Gaussian Process Regression

    NASA Astrophysics Data System (ADS)

    Mauerberger, S.; Holschneider, M.

    2017-12-01

    A major application in seismology is the determination of seismic velocity models. Travel time measurements are putting an integral constraint on the velocity between source and receiver. We provide insight into travel time inversion from a correlation-based Bayesian point of view. Therefore, the concept of Gaussian process regression is adopted to estimate a velocity model. The non-linear travel time integral is approximated by a 1st order Taylor expansion. A heuristic covariance describes correlations amongst observations and a priori model. That approach enables us to assess a proxy of the Bayesian posterior distribution at ordinary computational costs. No multi dimensional numeric integration nor excessive sampling is necessary. Instead of stacking the data, we suggest to progressively build the posterior distribution. Incorporating only a single evidence at a time accounts for the deficit of linearization. As a result, the most probable model is given by the posterior mean whereas uncertainties are described by the posterior covariance.As a proof of concept, a synthetic purely 1d model is addressed. Therefore a single source accompanied by multiple receivers is considered on top of a model comprising a discontinuity. We consider travel times of both phases - direct and reflected wave - corrupted by noise. Left and right of the interface are assumed independent where the squared exponential kernel serves as covariance.

  20. The van Hove distribution function for Brownian hard spheres: Dynamical test particle theory and computer simulations for bulk dynamics

    NASA Astrophysics Data System (ADS)

    Hopkins, Paul; Fortini, Andrea; Archer, Andrew J.; Schmidt, Matthias

    2010-12-01

    We describe a test particle approach based on dynamical density functional theory (DDFT) for studying the correlated time evolution of the particles that constitute a fluid. Our theory provides a means of calculating the van Hove distribution function by treating its self and distinct parts as the two components of a binary fluid mixture, with the "self " component having only one particle, the "distinct" component consisting of all the other particles, and using DDFT to calculate the time evolution of the density profiles for the two components. We apply this approach to a bulk fluid of Brownian hard spheres and compare to results for the van Hove function and the intermediate scattering function from Brownian dynamics computer simulations. We find good agreement at low and intermediate densities using the very simple Ramakrishnan-Yussouff [Phys. Rev. B 19, 2775 (1979)] approximation for the excess free energy functional. Since the DDFT is based on the equilibrium Helmholtz free energy functional, we can probe a free energy landscape that underlies the dynamics. Within the mean-field approximation we find that as the particle density increases, this landscape develops a minimum, while an exact treatment of a model confined situation shows that for an ergodic fluid this landscape should be monotonic. We discuss possible implications for slow, glassy, and arrested dynamics at high densities.

  1. Three-dimensional geoelectric modelling with optimal work/accuracy rate using an adaptive wavelet algorithm

    NASA Astrophysics Data System (ADS)

    Plattner, A.; Maurer, H. R.; Vorloeper, J.; Dahmen, W.

    2010-08-01

    Despite the ever-increasing power of modern computers, realistic modelling of complex 3-D earth models is still a challenging task and requires substantial computing resources. The overwhelming majority of current geophysical modelling approaches includes either finite difference or non-adaptive finite element algorithms and variants thereof. These numerical methods usually require the subsurface to be discretized with a fine mesh to accurately capture the behaviour of the physical fields. However, this may result in excessive memory consumption and computing times. A common feature of most of these algorithms is that the modelled data discretizations are independent of the model complexity, which may be wasteful when there are only minor to moderate spatial variations in the subsurface parameters. Recent developments in the theory of adaptive numerical solvers have the potential to overcome this problem. Here, we consider an adaptive wavelet-based approach that is applicable to a large range of problems, also including nonlinear problems. In comparison with earlier applications of adaptive solvers to geophysical problems we employ here a new adaptive scheme whose core ingredients arose from a rigorous analysis of the overall asymptotically optimal computational complexity, including in particular, an optimal work/accuracy rate. Our adaptive wavelet algorithm offers several attractive features: (i) for a given subsurface model, it allows the forward modelling domain to be discretized with a quasi minimal number of degrees of freedom, (ii) sparsity of the associated system matrices is guaranteed, which makes the algorithm memory efficient and (iii) the modelling accuracy scales linearly with computing time. We have implemented the adaptive wavelet algorithm for solving 3-D geoelectric problems. To test its performance, numerical experiments were conducted with a series of conductivity models exhibiting varying degrees of structural complexity. Results were compared with a non-adaptive finite element algorithm, which incorporates an unstructured mesh to best-fitting subsurface boundaries. Such algorithms represent the current state-of-the-art in geoelectric modelling. An analysis of the numerical accuracy as a function of the number of degrees of freedom revealed that the adaptive wavelet algorithm outperforms the finite element solver for simple and moderately complex models, whereas the results become comparable for models with high spatial variability of electrical conductivities. The linear dependence of the modelling error and the computing time proved to be model-independent. This feature will allow very efficient computations using large-scale models as soon as our experimental code is optimized in terms of its implementation.

  2. Excess Cancers Among HIV-Infected People in the United States

    PubMed Central

    Pfeiffer, Ruth M.; Shiels, Meredith S.; Li, Jianmin; Hall, H. Irene; Engels, Eric A.

    2015-01-01

    Background: Nearly 900 000 people in the United States are living with diagnosed human immunodeficiency virus (HIV) infection and therefore increased cancer risk. The total number of cancers occurring among HIV-infected people and the excess number above expected background cases are unknown. Methods: We derived cancer incidence rates for the United States HIV-infected and general populations from Poisson models applied to linked HIV and cancer registry data and from Surveillance, Epidemiology, and End Results program data, respectively. We applied these rates to estimates of people living with diagnosed HIV at mid-year 2010 to estimate total and expected cancer counts, respectively. We subtracted expected from total cancers to estimate excess cancers. Results: An estimated 7760 (95% confidence interval [CI] = 7330 to 8320) cancers occurred in 2010 among HIV-infected people, of which 3920 cancers (95% CI = 3480 to 4470) or 50% (95% CI = 48 to 54%) were in excess of expected. The most common excess cancers were non-Hodgkin’s lymphoma (NHL; n = 1440 excess cancers, occurring in 88% excess), Kaposi’s sarcoma (KS, n = 910, 100% excess), anal cancer (n = 740, 97% excess), and lung cancer (n = 440, 52% excess). The proportion of excess cancers that were AIDS defining (ie, KS, NHL, cervical cancer) declined with age and time since AIDS diagnosis (both P < .001). For anal cancer, 83% of excess cases occurred among men who have sex with men, and 71% among those living five or more years since AIDS onset. Among injection drug users, 22% of excess cancers were lung cancer, and 16% were liver cancer. Conclusions: The excess cancer burden in the US HIV population is substantial, and patterns across groups highlight opportunities for cancer control initiatives targeted to HIV-infected people. PMID:25663691

  3. What Is Known About the Correlates and Impact of Excess Skin After Bariatric Surgery: a Scoping Review.

    PubMed

    Baillot, Aurélie; Brais-Dussault, Elsa; Bastin, Anne; Cyr, Caroline; Brunet, Jennifer; Aimé, Annie; Romain, Ahmed J; Langlois, Marie-France; Bouchard, Stéphane; Tchernof, André; Rabasa-Lhoret, Rémi; Garneau, Pierre-Yves; Bernard, Paquito

    2017-09-01

    Although bariatric surgery (BS) improves health among adults with severe obesity, it results in excess skin in more than 70% of adults. The purpose of this study was to synthesize current knowledge on (1) the impact of excess skin experienced by adults after BS and (2) the correlates of excess skin quantity and inconveniences. PubMed, PsyArticles, and CINAHL databases were searched in May 2016 for relevant studies. Titles, abstracts, and full texts of studies retrieved were screened independently by two reviewers against inclusion criteria: (1) peer-reviewed primary research studies, (2) samples with adults who underwent BS, and (3) studies reporting the impact of excess skin and/or excess skin correlates. Thirteen quantitative and eleven qualitative studies met inclusion criteria. Negative physical, psychosocial, and daily life impacts of excess skin were reported in 67, 75, and 83% of studies, respectively. Women reported more excess skin and greater inconveniences of excess skin than did men. Based on the quantitative studies, pre-BS BMI, time since BS, and type of BS were not significantly associated with inconveniences of excess skin; findings were inconclusive for other correlates found (e.g. age, weight loss, BMI). Excess skin may adversely impact adults' physical and psychosocial functioning, as well as their activities of daily life after BS. However, evidence is lacking to determine which adults may be at heightened risk of developing or being negatively impacted by excess skin. More research on correlates of excess skill is needed to inform the development of tailored interventions in those more vulnerable to developing excess skin after BS to mitigate adverse consequences.

  4. Excess cancers among HIV-infected people in the United States.

    PubMed

    Robbins, Hilary A; Pfeiffer, Ruth M; Shiels, Meredith S; Li, Jianmin; Hall, H Irene; Engels, Eric A

    2015-04-01

    Nearly 900 000 people in the United States are living with diagnosed human immunodeficiency virus (HIV) infection and therefore increased cancer risk. The total number of cancers occurring among HIV-infected people and the excess number above expected background cases are unknown. We derived cancer incidence rates for the United States HIV-infected and general populations from Poisson models applied to linked HIV and cancer registry data and from Surveillance, Epidemiology, and End Results program data, respectively. We applied these rates to estimates of people living with diagnosed HIV at mid-year 2010 to estimate total and expected cancer counts, respectively. We subtracted expected from total cancers to estimate excess cancers. An estimated 7760 (95% confidence interval [CI] = 7330 to 8320) cancers occurred in 2010 among HIV-infected people, of which 3920 cancers (95% CI = 3480 to 4470) or 50% (95% CI = 48 to 54%) were in excess of expected. The most common excess cancers were non-Hodgkin's lymphoma (NHL; n = 1440 excess cancers, occurring in 88% excess), Kaposi's sarcoma (KS, n = 910, 100% excess), anal cancer (n = 740, 97% excess), and lung cancer (n = 440, 52% excess). The proportion of excess cancers that were AIDS defining (ie, KS, NHL, cervical cancer) declined with age and time since AIDS diagnosis (both P < .001). For anal cancer, 83% of excess cases occurred among men who have sex with men, and 71% among those living five or more years since AIDS onset. Among injection drug users, 22% of excess cancers were lung cancer, and 16% were liver cancer. The excess cancer burden in the US HIV population is substantial, and patterns across groups highlight opportunities for cancer control initiatives targeted to HIV-infected people. Published by Oxford University Press 2015.

  5. Adopting epidemic model to optimize medication and surgical intervention of excess weight

    NASA Astrophysics Data System (ADS)

    Sun, Ruoyan

    2017-01-01

    We combined an epidemic model with an objective function to minimize the weighted sum of people with excess weight and the cost of a medication and surgical intervention in the population. The epidemic model is consisted of ordinary differential equations to describe three subpopulation groups based on weight. We introduced an intervention using medication and surgery to deal with excess weight. An objective function is constructed taking into consideration the cost of the intervention as well as the weight distribution of the population. Using empirical data, we show that fixed participation rate reduces the size of obese population but increases the size for overweight. An optimal participation rate exists and decreases with respect to time. Both theoretical analysis and empirical example confirm the existence of an optimal participation rate, u*. Under u*, the weighted sum of overweight (S) and obese (O) population as well as the cost of the program is minimized. This article highlights the existence of an optimal participation rate that minimizes the number of people with excess weight and the cost of the intervention. The time-varying optimal participation rate could contribute to designing future public health interventions of excess weight.

  6. A near-infrared interferometric survey of debris-disc stars. V. PIONIER search for variability

    NASA Astrophysics Data System (ADS)

    Ertel, S.; Defrère, D.; Absil, O.; Le Bouquin, J.-B.; Augereau, J.-C.; Berger, J.-P.; Blind, N.; Bonsor, A.; Lagrange, A.-M.; Lebreton, J.; Marion, L.; Milli, J.; Olofsson, J.

    2016-10-01

    Context. Extended circumstellar emission has been detected within a few 100 milli-arcsec around ≳10% of nearby main sequence stars using near-infrared interferometry. Follow-up observations using other techniques, should they yield similar results or non-detections, can provide strong constraints on the origin of the emission. They can also reveal the variability of the phenomenon. Aims: We aim to demonstrate the persistence of the phenomenon over the timescale of a few years and to search for variability of our previously detected excesses. Methods: Using Very Large Telescope Interferometer (VLTI)/Precision Integrated Optics Near Infrared ExpeRiment (PIONIER) in H band we have carried out multi-epoch observations of the stars for which a near-infrared excess was previously detected using the same observation technique and instrument. The detection rates and distribution of the excesses from our original survey and the follow-up observations are compared statistically. A search for variability of the excesses in our time series is carried out based on the level of the broadband excesses. Results: In 12 of 16 follow-up observations, an excess is re-detected with a significance of > 2σ, and in 7 of 16 follow-up observations significant excess (> 3σ) is re-detected. We statistically demonstrate with very high confidence that the phenomenon persists for the majority of the systems. We also present the first detection of potential variability in two sources. Conclusions: We conclude that the phenomenon responsible for the excesses persists over the timescale of a few years for the majority of the systems. However, we also find that variability intrinsic to a target can cause it to have no significant excess at the time of a specific observation. Based on observations made with ESO Telescopes at the La Silla Paranal Observatory under program IDs 088.C-0266, 089.C-0365, 090.C-0526, 091.C-0576, 091.C-0597, 094.C-0232, and commissioning data.

  7. Benchmark calculations of excess electrons in water cluster cavities: balancing the addition of atom-centered diffuse functions versus floating diffuse functions.

    PubMed

    Zhang, Changzhe; Bu, Yuxiang

    2016-09-14

    Diffuse functions have been proved to be especially crucial for the accurate characterization of excess electrons which are usually bound weakly in intermolecular zones far away from the nuclei. To examine the effects of diffuse functions on the nature of the cavity-shaped excess electrons in water cluster surroundings, both the HOMO and LUMO distributions, vertical detachment energies (VDEs) and visible absorption spectra of two selected (H2O)24(-) isomers are investigated in the present work. Two main types of diffuse functions are considered in calculations including the Pople-style atom-centered diffuse functions and the ghost-atom-based floating diffuse functions. It is found that augmentation of atom-centered diffuse functions contributes to a better description of the HOMO (corresponding to the VDE convergence), in agreement with previous studies, but also leads to unreasonable diffuse characters of the LUMO with significant red-shifts in the visible spectra, which is against the conventional point of view that the more the diffuse functions, the better the results. The issue of designing extra floating functions for excess electrons has also been systematically discussed, which indicates that the floating diffuse functions are necessary not only for reducing the computational cost but also for improving both the HOMO and LUMO accuracy. Thus, the basis sets with a combination of partial atom-centered diffuse functions and floating diffuse functions are recommended for a reliable description of the weakly bound electrons. This work presents an efficient way for characterizing the electronic properties of weakly bound electrons accurately by balancing the addition of atom-centered diffuse functions and floating diffuse functions and also by balancing the computational cost and accuracy of the calculated results, and thus is very useful in the relevant calculations of various solvated electron systems and weakly bound anionic systems.

  8. Clinical assessment of excessive daytime sleepiness in the diagnosis of sleep disorders.

    PubMed

    Rosenberg, Russell P

    2015-12-01

    Daytime sleepiness is common, but, in some individuals, it can be excessive and lead to distress and impairment. For many of these individuals, excessive daytime sleepiness is simply caused by poor sleep habits or self-imposed sleep times that are not sufficient to maintain alertness throughout the day. For others, daytime sleepiness may be related to a more serious disorder or condition such as narcolepsy, idiopathic hypersomnia, or obstructive sleep apnea. Clinicians must be familiar with the disorders associated with excessive daytime sleepiness and the assessment methods used to diagnose these disorders in order to identify patients who need treatment. © Copyright 2015 Physicians Postgraduate Press, Inc.

  9. Two stage gear tooth dynamics program

    NASA Technical Reports Server (NTRS)

    Boyd, Linda S.

    1989-01-01

    The epicyclic gear dynamics program was expanded to add the option of evaluating the tooth pair dynamics for two epicyclic gear stages with peripheral components. This was a practical extension to the program as multiple gear stages are often used for speed reduction, space, weight, and/or auxiliary units. The option was developed for either stage to be a basic planetary, star, single external-external mesh, or single external-internal mesh. The two stage system allows for modeling of the peripherals with an input mass and shaft, an output mass and shaft, and a connecting shaft. Execution of the initial test case indicated an instability in the solution with the tooth paid loads growing to excessive magnitudes. A procedure to trace the instability is recommended as well as a method of reducing the program's computation time by reducing the number of boundary condition iterations.

  10. Double throat pressure pulsation dampener for oil-free screw compressors

    NASA Astrophysics Data System (ADS)

    Lucas, Michael J.

    2005-09-01

    This paper describes a recent invention at Ingersoll-Rand for reducing the pressure pulsations in an oil-free screw compressor. Pressure pulsation is a term used in the air compressor industry to describe the rapid change in pressure with time measured in the downstream piping of the air compressor. The pulsations are due to the rapid opening and closing of the screws as the compressed air is eject from the compressor into the piping system. The pulsations are known to produce excessive noise levels and high levels of vibration in the piping system. Reducing these pulsations is critical to achieving a quiet running compressor. This paper will describe the methodology used to analyze the data and show both computational and experimental results achieved using the pulsation dampener. A patent for this design has been filed with the US patent office.

  11. Evaluation of abutment scour prediction equations with field data

    USGS Publications Warehouse

    Benedict, S.T.; Deshpande, N.; Aziz, N.M.

    2007-01-01

    The U.S. Geological Survey, in cooperation with FHWA, compared predicted abutment scour depths, computed with selected predictive equations, with field observations collected at 144 bridges in South Carolina and at eight bridges from the National Bridge Scour Database. Predictive equations published in the 4th edition of Evaluating Scour at Bridges (Hydraulic Engineering Circular 18) were used in this comparison, including the original Froehlich, the modified Froehlich, the Sturm, the Maryland, and the HIRE equations. The comparisons showed that most equations tended to provide conservative estimates of scour that at times were excessive (as large as 158 ft). Equations also produced underpredictions of scour, but with less frequency. Although the equations provide an important resource for evaluating abutment scour at bridges, the results of this investigation show the importance of using engineering judgment in conjunction with these equations.

  12. Elements of decisional dynamics: An agent-based approach applied to artificial financial market

    NASA Astrophysics Data System (ADS)

    Lucas, Iris; Cotsaftis, Michel; Bertelle, Cyrille

    2018-02-01

    This paper introduces an original mathematical description for describing agents' decision-making process in the case of problems affected by both individual and collective behaviors in systems characterized by nonlinear, path dependent, and self-organizing interactions. An application to artificial financial markets is proposed by designing a multi-agent system based on the proposed formalization. In this application, agents' decision-making process is based on fuzzy logic rules and the price dynamics is purely deterministic according to the basic matching rules of a central order book. Finally, while putting most parameters under evolutionary control, the computational agent-based system is able to replicate several stylized facts of financial time series (distributions of stock returns showing a heavy tail with positive excess kurtosis, absence of autocorrelations in stock returns, and volatility clustering phenomenon).

  13. Elements of decisional dynamics: An agent-based approach applied to artificial financial market.

    PubMed

    Lucas, Iris; Cotsaftis, Michel; Bertelle, Cyrille

    2018-02-01

    This paper introduces an original mathematical description for describing agents' decision-making process in the case of problems affected by both individual and collective behaviors in systems characterized by nonlinear, path dependent, and self-organizing interactions. An application to artificial financial markets is proposed by designing a multi-agent system based on the proposed formalization. In this application, agents' decision-making process is based on fuzzy logic rules and the price dynamics is purely deterministic according to the basic matching rules of a central order book. Finally, while putting most parameters under evolutionary control, the computational agent-based system is able to replicate several stylized facts of financial time series (distributions of stock returns showing a heavy tail with positive excess kurtosis, absence of autocorrelations in stock returns, and volatility clustering phenomenon).

  14. Technique for Very High Order Nonlinear Simulation and Validation

    NASA Technical Reports Server (NTRS)

    Dyson, Rodger W.

    2001-01-01

    Finding the sources of sound in large nonlinear fields via direct simulation currently requires excessive computational cost. This paper describes a simple technique for efficiently solving the multidimensional nonlinear Euler equations that significantly reduces this cost and demonstrates a useful approach for validating high order nonlinear methods. Up to 15th order accuracy in space and time methods were compared and it is shown that an algorithm with a fixed design accuracy approaches its maximal utility and then its usefulness exponentially decays unless higher accuracy is used. It is concluded that at least a 7th order method is required to efficiently propagate a harmonic wave using the nonlinear Euler equations to a distance of 5 wavelengths while maintaining an overall error tolerance that is low enough to capture both the mean flow and the acoustics.

  15. Mortality among workers monitored for radiation exposure at the French nuclear fuel company.

    PubMed

    Metz-Flamant, C; Rogel, A; Caër, S; Samson, E; Laurier, D; Acker, A; Tirmarche, M

    2009-01-01

    A cohort of 9,285 nuclear workers employed at the French company AREVA NC specializing in the nuclear fuel cycle was established. Vital status, causes of death, employment characteristics and annual exposure to ionizing radiation were reconstructed for each individual over the time period 1977-2004. Standardized mortality ratios (SMRs) were computed using national mortality rates as an external reference. Tests for trends in mortality with duration of employment and cumulative external dose were performed. The all-cause and all-cancer mortality was significantly lower than expected from the French population. No significant excess among cancer sites studied was observed. Significant positive trends with cumulative dose were observed for colon and liver cancer and for respiratory diseases. Isolated significant trends should be carefully interpreted and considered in line with the large number of trend tests performed.

  16. Excess Costs Associated with Possible Misdiagnosis of Alzheimer’s Disease Among Patients with Vascular Dementia in a UK CPRD Population

    PubMed Central

    Happich, Michael; Kirson, Noam Y.; Desai, Urvi; King, Sarah; Birnbaum, Howard G.; Reed, Catherine; Belger, Mark; Lenox-Smith, Alan; Price, David

    2016-01-01

    Background: Prior diagnosis of Alzheimer’s disease (AD) among patients later diagnosed with vascular dementia (VaD) has been associated with excess costs, suggesting potential benefits of earlier rule-out of AD diagnosis. Objective: To investigate whether prior diagnosis with AD among patients with VaD is associated with excess costs in the UK. Methods: Patients with a final VaD diagnosis, continuous data visibility for≥6 months prior to index date, and linkage to Hospital Episode Statistics data were retrospectively selected from de-identified Clinical Practice Research Datalink data. Patients with AD diagnosis before a final VaD diagnosis were matched to similar patients with no prior AD diagnosis using propensity score methods. Annual excess healthcare costs were calculated for 5 years post-index, stratified by time to final diagnosis. Results: Of 9,311 patients with VaD, 508 (6%) had prior AD diagnosis with a median time to VaD diagnosis exceeding 2 years from index date. Over the entire follow-up period, patients with prior AD diagnosis had accumulated healthcare costs that were approximately GBP2,000 higher than those for matched counterparts (mostly due to higher hospitalization costs). Cost differentials peaked particularly in the period including the final VaD diagnosis, with excess costs quickly declining thereafter. Conclusion: Potential misdiagnosis of AD among UK patients with VaD resulted in substantial excess costs. The decline in excess costs following a final VaD diagnosis suggests potential benefits from earlier rule-out of AD. PMID:27163798

  17. 41 CFR 102-75.85 - Can disposal agencies transfer excess real property to agencies for programs that appear to be...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... further Federal utilization or disposal as surplus property at an agreed upon time when the transfer is... PROPERTY DISPOSAL Utilization of Excess Real Property Guidelines § 102-75.85 Can disposal agencies transfer...

  18. Plasmonic field confinement for separate absorption-multiplication in InGaAs nanopillar avalanche photodiodes

    PubMed Central

    Farrell, Alan C.; Senanayake, Pradeep; Hung, Chung-Hong; El-Howayek, Georges; Rajagopal, Abhejit; Currie, Marc; Hayat, Majeed M.; Huffaker, Diana L.

    2015-01-01

    Avalanche photodiodes (APDs) are essential components in quantum key distribution systems and active imaging systems requiring both ultrafast response time to measure photon time of flight and high gain to detect low photon flux. The internal gain of an APD can improve system signal-to-noise ratio (SNR). Excess noise is typically kept low through the selection of material with intrinsically low excess noise, using separate-absorption-multiplication (SAM) heterostructures, or taking advantage of the dead-space effect using thin multiplication regions. In this work we demonstrate the first measurement of excess noise and gain-bandwidth product in III–V nanopillars exhibiting substantially lower excess noise factors compared to bulk and gain-bandwidth products greater than 200 GHz. The nanopillar optical antenna avalanche detector (NOAAD) architecture is utilized for spatially separating the absorption region from the avalanche region via the NOA resulting in single carrier injection without the use of a traditional SAM heterostructure. PMID:26627932

  19. Turbulence modeling of free shear layers for high performance aircraft

    NASA Technical Reports Server (NTRS)

    Sondak, Douglas

    1993-01-01

    In many flowfield computations, accuracy of the turbulence model employed is frequently a limiting factor in the overall accuracy of the computation. This is particularly true for complex flowfields such as those around full aircraft configurations. Free shear layers such as wakes, impinging jets (in V/STOL applications), and mixing layers over cavities are often part of these flowfields. Although flowfields have been computed for full aircraft, the memory and CPU requirements for these computations are often excessive. Additional computer power is required for multidisciplinary computations such as coupled fluid dynamics and conduction heat transfer analysis. Massively parallel computers show promise in alleviating this situation, and the purpose of this effort was to adapt and optimize CFD codes to these new machines. The objective of this research effort was to compute the flowfield and heat transfer for a two-dimensional jet impinging normally on a cool plate. The results of this research effort were summarized in an AIAA paper titled 'Parallel Implementation of the k-epsilon Turbulence Model'. Appendix A contains the full paper.

  20. Sleep problems and computer use during work and leisure: Cross-sectional study among 7800 adults.

    PubMed

    Andersen, Lars Louis; Garde, Anne Helene

    2015-01-01

    Previous studies linked heavy computer use to disturbed sleep. This study investigates the association between computer use during work and leisure and sleep problems in working adults. From the 2010 round of the Danish Work Environment Cohort Study, currently employed wage earners on daytime schedule (N = 7883) replied to the Bergen insomnia scale and questions on weekly duration of computer use. Results showed that sleep problems for three or more days per week (average of six questions) were experienced by 14.9% of the respondents. Logistic regression analyses, controlled for gender, age, physical and psychosocial work factors, lifestyle, chronic disease and mental health showed that computer use during leisure for 30 or more hours per week (reference 0-10 hours per week) was associated with increased odds of sleep problems (OR 1.83 [95% CI 1.06-3.17]). Computer use during work and shorter duration of computer use during leisure were not associated with sleep problems. In conclusion, excessive computer use during leisure - but not work - is associated with sleep problems in adults working on daytime schedule.

  1. Leisure-Time Physical Activity and Sedentary Behavior and Their Cross-Sectional Associations with Excessive Daytime Sleepiness in the French SU.VI.MAX-2 Study.

    PubMed

    Andrianasolo, Roland M; Menai, Mehdi; Galan, Pilar; Hercberg, Serge; Oppert, Jean-Michel; Kesse-Guyot, Emmanuelle; Andreeva, Valentina A

    2016-04-01

    The potential benefit of physical activity in terms of decreasing excessive daytime sleepiness (EDS) prevalence is unclear, especially in aging adults. We aimed to elucidate the associations among physical activity, sedentariness, and EDS in middle-aged and older adults. We conducted a cross-sectional analysis using data from a subsample of participants in the SU.VI.MAX-2 observational study (2007-2009; N = 4179; mean age = 61.9 years). EDS was defined as a score >10 on the Epworth Sleepiness Scale. Leisure-time physical activity and different types of sedentary behavior were assessed with the Modifiable Activity Questionnaire. The associations were examined with multivariable logistic regression models. In the adjusted multivariable model, total leisure-time physical activity (modeled in quartiles, Q) was significantly, inversely associated with EDS (odds ratios (OR)Q4 vs Q1 = 0.70, 95 % confidence interval (CI) = 0.54-0.89). The association persisted in analyses restricted to individuals not taking sleep medication (ORQ4 vs Q1 = 0.72, 95 % CI = 0.54-0.95). In turn, time spent watching television and time spent reading appeared protective against EDS (ORQ4 vs Q1 = 0.73, 95 % CI = 0.57-0.94; ORQ4 vs Q1 = 0.76, 95 % CI = 0.60-0.97, respectively), whereas time spent on a computer appeared to confer an increased risk for EDS (ORQ4 vs Q1 = 1.30, 95 % CI = 1.05-1.62). When physical activity and sedentariness were modeled jointly, using WHO recommendation-based cutoffs for high/low levels, no significant associations were observed in the fully adjusted models. The findings reinforce public health recommendations promoting behavior modification and specifically moderate-intensity exercise in middle-aged and older adults. The association of high physical activity/low sedentariness with EDS, which was not supported by the data, merits further investigation before firm conclusions could be drawn.

  2. Spatial and seasonal patterns in urban influence on regional concentrations of speciated aerosols across the United States

    NASA Astrophysics Data System (ADS)

    Hand, J. L.; Schichtel, B. A.; Malm, W. C.; Pitchford, M.; Frank, N. H.

    2014-11-01

    Monthly, seasonal, and annual mean estimates of urban influence on regional concentrations of major aerosol species were computed using speciated aerosol data from the rural IMPROVE network (Interagency Monitoring of Protected Visual Environments) and the United States Environmental Protection Agency's urban Chemical Speciation Network for the 2008 through 2011 period. Aggregated for sites across the continental United States, the annual mean and one standard error in urban excess (defined as the ratio of urban to nearby rural concentrations) was highest for elemental carbon (3.3 ± 0.2), followed by ammonium nitrate (2.5 ± 0.2), particulate organic matter (1.78 ± 0.08), and ammonium sulfate (1.23 ± 0.03). The seasonal variability in urban excess was significant for carbonaceous aerosols and ammonium nitrate in the West, in contrast to the low seasonal variability in the urban influence of ammonium sulfate. Generally for all species, higher excess values in the West were associated with localized urban sources while in the East excess was more regional in extent. In addition, higher excess values in the western United States in winter were likely influenced not only by differences in sources but also by combined meteorological and topographic effects. This work has implications for understanding the spatial heterogeneity of major aerosol species near the interface of urban and rural regions and therefore for designing appropriate air quality management strategies. In addition, the spatial patterns in speciated mass concentrations provide constraints for regional and global models.

  3. On the physical origins of interaction-induced vibrational (hyper)polarizabilities.

    PubMed

    Zaleśny, Robert; Garcia-Borràs, Marc; Góra, Robert W; Medved', Miroslav; Luis, Josep M

    2016-08-10

    This paper presents the results of a pioneering exploration of the physical origins of vibrational contributions to the interaction-induced electric properties of molecular complexes. In order to analyze the excess nuclear relaxation (hyper)polarizabilities, a new scheme was proposed which relies on the computationally efficient Bishop-Hasan-Kirtman method for determining the nuclear relaxation contributions to electric properties. The extension presented herein is general and can be used with any interaction-energy partitioning method. As an example, in this study we employed the variational-perturbational interaction-energy decomposition scheme (at the MP2/aug-cc-pVQZ level) and the extended transition state method by employing three exchange-correlation functionals (BLYP, LC-BLYP, and LC-BLYP-dDsC) to study the excess properties of the HCN dimer. It was observed that the first-order electrostatic contribution to the excess nuclear relaxation polarizability cancels with the negative exchange repulsion term out to a large extent, resulting in a positive value of Δα(nr) due to the contributions from the delocalization and the dispersion terms. In the case of the excess nuclear relaxation first hyperpolarizability, the pattern of interaction contributions is very similar to that for Δα(nr), both in terms of their sign as well as relative magnitude. Finally, our results show that the LC-BLYP and LC-BLYP-dDsC functionals, which yield smaller values of the orbital relaxation term than BLYP, are more successful in predicting excess properties.

  4. Differential mortality in New York City (1988-1992). Part One: excess mortality among non-Hispanic blacks.

    PubMed

    Fang, J; Madhavan, S; Cohen, H; Alderman, M H

    1995-01-01

    To determine the distribution of mortality for non-Hispanic blacks and non-Hispanic whites in New York City, death certificates issued in New York City during 1988 through 1992, and the relevant 1990 US census data for New York City, have been examined. Age-adjusted death rates for blacks and whites by gender and cause of death were computed based on the US population in 1940. Also, standard mortality ratios and excess mortality were calculated using the New York City mortality rate as reference. The results showed that New York City blacks had higher age-adjusted death rates than whites regardless of cause, including stroke, AIDS, homicide, and diabetes. The rate for New York City blacks was also higher than the US total for both genders. Using New York City mortality rates as a reference, more than 80% of excess deaths in blacks occurred before age 65. Injury/poisoning was the leading cause of excess death (20.1%) in black males, while in black females, cardiovascular disease was the largest single cause of excess deaths (24.8%). The higher death rates, especially premature death, of blacks in New York City are related to conditions such as violence, substance abuse, and AIDS, for which prevention rather than medical care is the more likely solution, as well as to cardiovascular diseases, where both prevention through behavioral change, and health and medical care, can influence outcome.

  5. Zero-inflated spatio-temporal models for disease mapping.

    PubMed

    Torabi, Mahmoud

    2017-05-01

    In this paper, our aim is to analyze geographical and temporal variability of disease incidence when spatio-temporal count data have excess zeros. To that end, we consider random effects in zero-inflated Poisson models to investigate geographical and temporal patterns of disease incidence. Spatio-temporal models that employ conditionally autoregressive smoothing across the spatial dimension and B-spline smoothing over the temporal dimension are proposed. The analysis of these complex models is computationally difficult from the frequentist perspective. On the other hand, the advent of the Markov chain Monte Carlo algorithm has made the Bayesian analysis of complex models computationally convenient. Recently developed data cloning method provides a frequentist approach to mixed models that is also computationally convenient. We propose to use data cloning, which yields to maximum likelihood estimation, to conduct frequentist analysis of zero-inflated spatio-temporal modeling of disease incidence. One of the advantages of the data cloning approach is that the prediction and corresponding standard errors (or prediction intervals) of smoothing disease incidence over space and time is easily obtained. We illustrate our approach using a real dataset of monthly children asthma visits to hospital in the province of Manitoba, Canada, during the period April 2006 to March 2010. Performance of our approach is also evaluated through a simulation study. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. An energy-efficient failure detector for vehicular cloud computing.

    PubMed

    Liu, Jiaxi; Wu, Zhibo; Dong, Jian; Wu, Jin; Wen, Dongxin

    2018-01-01

    Failure detectors are one of the fundamental components for maintaining the high availability of vehicular cloud computing. In vehicular cloud computing, lots of RSUs are deployed along the road to improve the connectivity. Many of them are equipped with solar battery due to the unavailability or excess expense of wired electrical power. So it is important to reduce the battery consumption of RSU. However, the existing failure detection algorithms are not designed to save battery consumption RSU. To solve this problem, a new energy-efficient failure detector 2E-FD has been proposed specifically for vehicular cloud computing. 2E-FD does not only provide acceptable failure detection service, but also saves the battery consumption of RSU. Through the comparative experiments, the results show that our failure detector has better performance in terms of speed, accuracy and battery consumption.

  7. An energy-efficient failure detector for vehicular cloud computing

    PubMed Central

    Liu, Jiaxi; Wu, Zhibo; Wu, Jin; Wen, Dongxin

    2018-01-01

    Failure detectors are one of the fundamental components for maintaining the high availability of vehicular cloud computing. In vehicular cloud computing, lots of RSUs are deployed along the road to improve the connectivity. Many of them are equipped with solar battery due to the unavailability or excess expense of wired electrical power. So it is important to reduce the battery consumption of RSU. However, the existing failure detection algorithms are not designed to save battery consumption RSU. To solve this problem, a new energy-efficient failure detector 2E-FD has been proposed specifically for vehicular cloud computing. 2E-FD does not only provide acceptable failure detection service, but also saves the battery consumption of RSU. Through the comparative experiments, the results show that our failure detector has better performance in terms of speed, accuracy and battery consumption. PMID:29352282

  8. Performance of the Cell processor for biomolecular simulations

    NASA Astrophysics Data System (ADS)

    De Fabritiis, G.

    2007-06-01

    The new Cell processor represents a turning point for computing intensive applications. Here, I show that for molecular dynamics it is possible to reach an impressive sustained performance in excess of 30 Gflops with a peak of 45 Gflops for the non-bonded force calculations, over one order of magnitude faster than a single core standard processor.

  9. 26 CFR 1.148-3 - General arbitrage rebate rules.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... at the end of any period is determined using the economic accrual method and equals the value of that..., when added to the future value, as of the computation date, of previous rebate payments made for the... any date, the rebate amount for an issue is the excess of the future value, as of that date, of all...

  10. 26 CFR 1.148-3 - General arbitrage rebate rules.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... at the end of any period is determined using the economic accrual method and equals the value of that..., when added to the future value, as of the computation date, of previous rebate payments made for the... any date, the rebate amount for an issue is the excess of the future value, as of that date, of all...

  11. 26 CFR 1.148-3 - General arbitrage rebate rules.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... at the end of any period is determined using the economic accrual method and equals the value of that..., when added to the future value, as of the computation date, of previous rebate payments made for the... any date, the rebate amount for an issue is the excess of the future value, as of that date, of all...

  12. 26 CFR 1.148-3 - General arbitrage rebate rules.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... at the end of any period is determined using the economic accrual method and equals the value of that..., when added to the future value, as of the computation date, of previous rebate payments made for the... any date, the rebate amount for an issue is the excess of the future value, as of that date, of all...

  13. 26 CFR 1.809-9 - Computation of the differential earnings rate and the recomputed differential earnings rate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED... the amount equal to the product of— (i) The life insurance company's average equity base for the... the excess of— (i) The imputed earnings rate for the taxable year; over (ii) The average mutual...

  14. 26 CFR 1.1502-2 - Computation of tax liability.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... reference to the excess of the consolidated net long-term capital gain over the consolidated net short-term capital loss (see § 1.1502-41A for the determination of the consolidated net long-term capital gain and the consolidated net short-term capital loss)); (i) [Reserved] (j) The tax imposed by section 1333 on...

  15. 26 CFR 1.1502-2 - Computation of tax liability.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... reference to the excess of the consolidated net long-term capital gain over the consolidated net short-term capital loss (see § 1.1502-41A for the determination of the consolidated net long-term capital gain and the consolidated net short-term capital loss)); (i) [Reserved] (j) The tax imposed by section 1333 on...

  16. 26 CFR 1.1502-2 - Computation of tax liability.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... reference to the excess of the consolidated net long-term capital gain over the consolidated net short-term capital loss (see § 1.1502-41A for the determination of the consolidated net long-term capital gain and the consolidated net short-term capital loss)); (i) [Reserved] (j) The tax imposed by section 1333 on...

  17. 26 CFR 1.1502-2 - Computation of tax liability.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... reference to the excess of the consolidated net long-term capital gain over the consolidated net short-term capital loss (see § 1.1502-41A for the determination of the consolidated net long-term capital gain and the consolidated net short-term capital loss)); (i) [Reserved] (j) The tax imposed by section 1333 on...

  18. 26 CFR 1.1502-2 - Computation of tax liability.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... reference to the excess of the consolidated net long-term capital gain over the consolidated net short-term capital loss (see § 1.1502-41A for the determination of the consolidated net long-term capital gain and the consolidated net short-term capital loss)); (i) [Reserved] (j) The tax imposed by section 1333 on...

  19. Decreasing Excessive Media Usage while Increasing Physical Activity: A Single-Subject Research Study

    ERIC Educational Resources Information Center

    Larwin, Karen H.; Larwin, David A.

    2008-01-01

    The Kaiser Family Foundation released a report entitled "Kids and Media Use" in the United States that concluded that children's use of media--including television, computers, Internet, video games, and phones--may be one of the primary contributor's to the poor fitness and obesity of many of today's adolescents. The present study examines the…

  20. Investigation of Electronic Generation of Visual Images for Air Force Technical Training. Interim Report for Period May 1974-October 1975.

    ERIC Educational Resources Information Center

    Filinger, Ronald H.; Hall, Paul W.

    Because large scale individualized learning systems place excessive demands on conventional means of producing audiovisual software, electronic image generation has been investigated as an alternative. A prototype, experimental device, Scanimate-500, was designed and built by the Computer Image Corporation. It uses photographic, television, and…

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